# Nemett Lynx 15 cc 4 Stroke I/C Petrol Engine



## gus

Plan to build this engine next year .Bought plans and the Best of Model Engineer,100 Page special Autumn 2013 Magazine.
Still wondering am I chewing off too much more than I can swallow and digest.Have I the all the required skills/determination to complete from scratch. Have not jumped in yet. Having very bad cold feet.
 Engine is about same overall dimension of Rupnow's Hit & Miss Engine but with overhead cam drive . Overall height is 165mm.
The magazine has very good write-up take reader thru step by step or rather
foto by foto. 
Hi Meisters/Maestros. Your kind advice is requested.


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## BronxFigs

Gus:

Only you could know your comfort level. 

How bad could this build be?  If you ruin a part, re-make it from bar-stock.  If you run into bad problems, the forum members will help you solve them.  I have these plans and even with my very rudimentary skills, I would attempt it.  The only parts that cause me some concern would be generating/profiling the cams, and maybe, the carb....oh yeah, valve seating and leaking.   But look at the beautiful engine that you'll be making, and all the new skills you'll be gaining.

GO  FOR IT!



Frank


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## Cogsy

Gus - from what I've seen of your work so far, I definitely think you can build this engine (although I'm not familiar with this engine at all). Plus, I find it very rewarding to learn new skills and do things that I haven't done before.

Speaking for myself, once I finish all my current engine projects , my next build will be a multi-cylinder 4 stroke. I'm not at all comfortable with my choice and I know I don't yet possess all the skills to build it, but I know with help from the forum geniuses, and with enough effort from me, I will get it to run.

Good luck with whatever you choose.


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## Paulsv

I have looked over the plan and articles, and hope to build one after I retire.  It is a litttle complicated, but the very complete builder notes that the articles give should make it a lot easier.   I'm sure you can do it, Gus, but I think it will be a big time commitmernt.  It sure is a beautiful engine.


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## Jasonb

Gus, did you ever get the Firefly going? There are far more important fits in the Lynx than the Firefly that you will need to achieve if it is to run OK.

J


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## Swifty

Gus, I think that I've mentioned before that we need challenges to hone our machining skills. I'm amazed by what you can produce with a balcony workshop. You should go for it, were all here to help.

I'm off to the newsagents this morning to see if I can get a copy of the magazine with the plans.

Paul.


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## Swifty

Checked several local shops that sell the magazine, but none have the special edition, so have placed an order to have one posted out.

Paul.


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## wheeltapper

Hi
I see no reason for you not to have a go at this engine.
I managed to build it and I class myself as a rank amateur,in fact its only the second engine I have made.
see here...http://www.homemodelenginemachinist.com/f14/nemett-15cc-4-stroke-engine-14425/

I might add that I built mine from the magazine articles and not the overexpensive book.

good luck.
Roy.


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## gus

Jasonb said:


> Gus, did you ever get the Firefly going? There are far more important fits in the Lynx than the Firefly that you will need to achieve if it is to run OK.
> 
> J



Hi Jason,

I have two very unforgiving engines to rework and get running.
The Bolero and the Firefly. After this engines are up and running,will go on to
the Nemett Lynx. Both Bolero and Firefly have some critical fits to meet.

With experience gained from both these two engines plus the Webster and 
Brian's H&M Engine,I would gain confidence to embark on the "Lynx" in 2014.

Thanks for the expert advice.


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## gus

wheeltapper said:


> Hi
> I see no reason for you not to have a go at this engine.
> I managed to build it and I class myself as a rank amateur,in fact its only the second engine I have made.
> see here...http://www.homemodelenginemachinist.com/f14/nemett-15cc-4-stroke-engine-14425/
> 
> I might add that I built mine from the magazine articles and not the overexpensive book.
> 
> good luck.
> Roy.




Hi Roy,
Saw your engine running beautifully sometime ago and I just could not resist not building this engine.  The Model Engineer article has very comprehensive Work Instructions as though written by ISO 9000 guys.
This will be the first time I will be cutting cam shafts with two cams.
Plan to run with petrol and CDI.Promise I will take time to make this engine and no rush.Will take time to read article and scrutinise prints. 

With the Firefly I went in like a Kamikaze fighter w/o comprehending the prints and crashed. Same engine has some very unforgiving fits.The Bolero too.
 As of last six months with the building of Webster and Brian's H & M Engine, my turning skills has improved vastly.

Now pondering to buy a new lathe now that Bernanke is behaving and the local market shot up. Gus made a good bundle.Also been spending on good turning tools and measuring instruments.Plan to throw away all the cheapy
China Mikes and Calipers that eat batteries and indicator panels flash like Christmas trees.


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## doubletop

Me too

I've got the best of ME articles, have sourced the bar stock and did the cylinder liner the other day. Small beginnings.

However, I'm now sourcing the bought in parts I went to HPC for the timing pulleys and belts and they are very expensive. Digging around I came across the 3D printing Wiki http://reprap.org/wiki/Belts_and_Pulleys and a good write up on various vendors. Take a look at www.beltingonline.com only 10quid for both the pulleys and belt.

For the bearings Arc Eurotrade prices look OK but they don't have needle roller inner sleeve.

*My question;* would it be OK to make the roller inner sleeve from a  10.5mm length  of 10mm Silver Steel, 7mm reamed hole, heated to cherry red and quenched in water?

Pete


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## wheeltapper

HI
Nice to see you made a start.
The bearing part really depends on what you are going to do with the engine when its finished. ( note I said when not if) 

If you are going to test run it the just display it silver steel should work , you'll have to temper it as well or it'll shatter.
If you intend to run it in a model I would go for the proper thing.

Have you looked here http://simplybearings.co.uk/shop/index.html.

I get most of my bearings here.

Good luck with the build and we want lots of pics.

If I can help in any way just yell.

Roy.


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## gus

doubletop said:


> Me too
> 
> I've got the best of ME articles, have sourced the bar stock and did the cylinder liner the other day. Small beginnings.
> 
> However, I'm now sourcing the bought in parts I went to HPC for the timing pulleys and belts and they are very expensive. Digging around I came across the 3D printing Wiki http://reprap.org/wiki/Belts_and_Pulleys and a good write up on various vendors. Take a look at www.beltingonline.com only 10quid for both the pulleys and belt.
> 
> For the bearings Arc Eurotrade prices look OK but they don't have needle roller inner sleeve.
> 
> *My question;* would it be OK to make the roller inner sleeve from a  10.5mm length  of 10mm Silver Steel, 7mm reamed hole, heated to cherry red and quenched in water?
> 
> Pete




Hi Pete,

I am up to my neck with Webster IC Engine and The Rupnow H & M Engine.
Got the H&M Engine going but I still have the Hit & Miss parts to be done. Will do it leisurely. Will be March 2014 before I start buy the timing belts.

Will be following your threads building the Nemett Engine. Plan to cut the timing belt wheels because they cost an arm and leg to buy. Cutting these wheel will be fun though I have successfully cut some small gears for the above engines with Harold Hall's Dividing Head.

Wish you all success.

Gus Teng,from faraway Singapore.


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## petertha

gus said:


> Plan to cut the timing belt wheels because they cost an arm and leg to buy..


 
I dont know much about these timing belts & pulleys supply, but I have seen smallish sized ones like this in robotics kits suppliers, link below. They seem very reasonably priced if they would work. The smallest circumference of toothed belt is 120mm (4.72"). Judging by the Nemett engine size, maybe something could be made to work from this selection? 

http://www.robotmarketplace.com/products/timing_belts_fingertech.html

http://www.robotmarketplace.com/products/timing_pulleys_fingertech.html
 
At the end of the day, I imaging all that's required is 2:1 gear ratio for the cam. It doesnt mater if they are metric or imperial, as long as the tooth pitch match the corresponding belt & gear ratio is 2:1?

Another possible source might be RC helicopters & cars. But I suspect the belts might always be too long for that application ... unless there is a reliable way to splice & join them?

http://dx.com/p/esky-ek1-0503-belt-parts-spare-for-belt-cp-v2-rc-helicopter-80cm-33375

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDHU7


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## doubletop

wheeltapper said:


> HI
> 
> Have you looked here http://simplybearings.co.uk/shop/index.html.
> 
> I get most of my bearings here.
> 
> 
> Roy.



Looks Like I do now 

Thanks for the tip

Pete


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## gus

petertha said:


> I dont know much about these timing belts & pulleys supply, but I have seen smallish sized ones like this in robotics kits suppliers, link below. They seem very reasonably priced if they would work. The smallest circumference of toothed belt is 120mm (4.72"). Judging by the Nemett engine size, maybe something could be made to work from this selection?
> 
> http://www.robotmarketplace.com/products/timing_belts_fingertech.html
> 
> http://www.robotmarketplace.com/products/timing_pulleys_fingertech.html
> 
> At the end of the day, I imaging all that's required is 2:1 gear ratio for the cam. It doesnt mater if they are metric or imperial, as long as the tooth pitch match the corresponding belt & gear ratio is 2:1?
> 
> Another possible source might be RC helicopters & cars. But I suspect the belts might always be too long for that application ... unless there is a reliable way to splice & join them?
> 
> http://dx.com/p/esky-ek1-0503-belt-parts-spare-for-belt-cp-v2-rc-helicopter-80cm-33375
> 
> http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDHU7



Hi Peter,

You are a gem. Thanks .The timing wheels are so cost effective. Will buy and study.

Now looking for belts. There are many belt shops here in Singapore.Failure of which will pay more for the UK source,


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## petertha

gus said:


> You are a gem. Thanks .The timing wheels are so cost effective. Will buy and study. Now looking for belts....


 
You're welcome. The belts is the first link! 
http://www.robotmarketplace.com/products/timing_belts_fingertech.html

You may as well buy them same time. Probably same combined shipping cost & they can be travel mates on long box trip journey Singapore!


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## zega79

hi
  I have just bought the latest model engineer with Lynx 15cc petro engine . I have checked the drawing and could not find any DIM tolerances for any dimensions. question is that anybody built this engine before and could help me to solve the  problem? many thanks mike


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## doubletop

Mike

As the guys have said over on Model Engineer. Unless you are making more than one and all the parts need to be interchangeable make one part to dimension and make the other part fit. You are your own Quality Controller.

Pete


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## Swifty

Zega79, I have the drawings for this motor and will start later this year. As Mike said, you have to make your own tolerances. Just work out what is easier, to make bores on size or to make the parts that go in them on size, and make other parts to suit.

Paul.


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## gus

Swifty said:


> Zega79, I have the drawings for this motor and will start later this year. As Mike said, you have to make your own tolerances. Just work out what is easier, to make bores on size or to make the parts that go in them on size, and make other parts to suit.
> 
> Paul.



Good advice given. The Lynx will be in the que after two old engine projects,namely Bolero and Firefly both have yet to be completed and run. Reason was -----lack experience to handle the unforgiving fits required.
Now in South Thailand after the Burma Bank Fishing Trip. Due  a temporary ban
,we were forced to go to other spots which overfished and hence not very productive. Catch was bad with nothing great to crow.


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## gus

While in South Thailand,to kill idle time,made B.O.M. and ordered some cut bar stocks .
For this project,will take time to study plans, Model Engineer Mag.Nemett-Lynx Article.
The author has lined up priority que for parts to be made.Messing up priority order will bring disorders as some parts need to pair up and fit in mutually.Will start with liner. Liner will be used
to closely slide fit cylinder jacket and in turn same jacket to fit crankcase etc etc. to optimise heat transfer.


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## gus

Collected bar stocks. Come next week will begin the begin. Will try hard not goofing. Salvaging a job is time consuming/stressful and time consuming.Bought more enough to build three engines.
Will start off as recommended to turn the cast iron liner and from here the cylinder jacket,cranlcase etc.
In these order the related vital fits met.


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## clivel

Hi Gus,
If you want to build the Lynx from the article in "Best of Model Engineer Vol 3" you should be aware that table for generating the cam was left out.

This thread on Model Engineer Forum contains the relevant information including a link to the original article in Model Engineer Sept 2006 page 282.

Clive


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## mikegw1961

Gus
If you want a copy of the page that was missing I have the original drawings and would be happy to email you a copy of the missing page

Mike


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## Brian Rupnow

Tell me--Does this engine have a sealed crankcase? I have now built 6 open crankcase engines, and the oil mess drives me crazy each time I run them. If the crankcase is sealed, does it have splash oiling, or are there oil passages drilled in the crankshaft?---Brian


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## gus

Brian Rupnow said:


> Tell me--Does this engine have a sealed crankcase? I have now built 6 open crankcase engines, and the oil mess drives me crazy each time I run them. If the crankcase is sealed, does it have splash oiling, or are there oil passages drilled in the crankshaft?---Brian



Has over-hung crankshaft and grease packed bearings.Still studying and asking questions. Been working on air compressors,lube oil in the crankcase leaking out is messy. Seen several engines running on YouTube.

I seen nothing sticking out from the con-rod big end.W/o which splash lubrication not well done. There is a breather tube from crankcase to OHC housing to lubricate cams. 

Paul and Gus will be building this engine. Will be fun.Paul will lead Gus.
Gus will follow Paul.


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## Jasonb

The con rod big end dips into the oil so that splashes it about and there is no need for a separate splasher.

Top end is lubricated by oil vapour going up the copper bit that joins the breather to the box the cam is in.


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## doubletop

Brian Rupnow said:


> Tell me--Does this engine have a sealed crankcase? I have now built 6 open crankcase engines, and the oil mess drives me crazy each time I run them. If the crankcase is sealed, does it have splash oiling, or are there oil passages drilled in the crankshaft?---Brian



Brian

It may be sealed but it does leak. I'm using a Walbro carb so need some crank case pressure for the pump. Net result is the oil migrates through the nose bearings, then on to the toothed belt, which then is lifted upwards to the camshaft. On the way the prop draft catches it then its blown aft. (yes there are oil seals on the bearings, but I don't wnat to glue them in. As soon as I do I'll need a strip down)

That's the oil that doesn't creep past the rings and out the exhaust. There's no oir scraper ring.

Who was it that was asking questions about fits?

Pete


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## gus

Jasonb said:


> The con rod big end dips into the oil so that splashes it about and there is no need for a separate splasher.
> 
> Top end is lubricated by oil vapour going up the copper bit that joins the breather to the box the cam is in.




Thanks Jason.

Please advise oil level. Planning to put in an Ingersoll-Rand Oil Level Sight Glass.. Now trying to finish up DIY Tool Cabinet .


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## mu38&Bg#

The big end uses a needle bearing so it doesn't need much oil. When buying bearings be certain that they are of the contact seal variety. What look like rubber seals can be non-contact shields and will not hold any oil. Even contact seals won't be able to hold back the oil in a closed single cylinder crankcase due to the constantly fluctuating pressure. You could add a shaft oil seal in front of the rear crank bearing to prevent oil from leaking out.

Greg


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## Brian Rupnow

Gus---I sent you a private message about this about 5 minutes ago.---Brian EDIT--Gus--I followed this link, and there are a lot of folks saying that the magazine article has a lot of mistakes in it, and that anyone considering building this engine should buy the plans, not rely on the magazine articles. Model Engineer Forum


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## Jasonb

Brian its the earlier 2006 edition that has a few errors, The one that Gus has in the "Best of" uses the revised drawings. Its only a bit of text in the Best of that does not agree with the drawings and the missing cam details that have already been covered.

Some useful photos 

here and here

J


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## doubletop

I built it from the "Best of Magazine" with few problems. Of course the missing cam data didn't help but Jason helped me out there. All the notes are contained in this thread

http://www.model-engineer.co.uk/forums/postings.asp?th=90027&p=1











Malcolms write up is very well done and makes it easy for a beginner to work out what they need to do.

Pete


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## doubletop

Brian 

I like your drawing, Jason had mentioned doing something similar. I had thought the Bobcat would easily be made as a flat 4 'boxer'. Although the problem with oil passing the pistons could prove an issue.

Pete


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## Swifty

clivel said:


> Hi Gus,
> If you want to build the Lynx from the article in "Best of Model Engineer Vol 3" you should be aware that table for generating the cam was left out.
> 
> This thread on Model Engineer Forum contains the relevant information including a link to the original article in Model Engineer Sept 2006 page 282.
> 
> Clive



My copy of the magazine certainly has the cam calcs, I have copied and enlarged all the drawings from the magazine to A3 size, that way it doesn't matter if they get dirty or damaged.

Paul.


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## gus

doubletop said:


> I built it from the "Best of Magazine" with few problems. Of course the missing cam data didn't help but Jason helped me out there. All the notes are contained in this thread
> 
> http://www.model-engineer.co.uk/forums/postings.asp?th=90027&p=1
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Malcolms write up is very well done and makes it easy for a beginner to work out what they need to do.
> 
> Pete



Hi Pete,
You are my hero/meister. When can we see video of running engine?
Will be late next week to start turning the C.I. Liner. Will proceed step by step as per Best of Magazine. Paul Swifty is about to get started. 

Would you be running with dry crankcase or lube oil topped up Crankcase?.


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## Brian Rupnow

I really do like the way the crankcase is machined from a block of aluminum in that design, and intended to be "oil-tight" (even if it really isn't according to posters.). I know that the timing belt drive for the camshaft works very well, because that is what I used on the Atkinson engine I built, but its a bit too "new age" for my taste.--Its probably just my age, but I like to see push rods pushing and rocker arms rocking. I'm not horribly impressed with the cantilevered crankshaft and no flywheel. The engine looks like a large model airplane engine, and that is not a bad thing---its just that I prefer a more industrial look. I am probably going to take that design and model/design a more industrial looking engine from it. This may not happen quickly, but it is probably the direction I will move in.---Brian


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## Jasonb

Pete, my opposed twin is under way so I'll let you know how the oil goes regarding the pistons and tappet guides.

Brian, I spent last weekend milling out the crankcase, first drilled to 1" dia then bored to 46mm on the lathe and finally milled to 47x48 x 57mm deep

J


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## BronxFigs

Love reading all the "private" thoughts, and comments from the more experienced engine builders.  I marvel that they can look at a basic concept, then, add cylinders, V-Twin it, add push-rods - where none existed, and revamp the whole shebang until it morphs into a "new" design.  Love the re-worked, computer renderings, and all the thinking-out-loud from the expert swarf-makers.

Congratulations, and thanks for sharing this build with us.  Guys like you advance this hobby.


Frank


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## Brian Rupnow

Bronx---There are some very smart builders out there. Most people who are well advanced in 3D design don't just want to copy someone else's engine. We want to add our own personal touch and design something that has never been done quite that way before. It is almost impossible to design something so totally new that it has never been done before by somebody, somewhere. Almost all "new" mechanical designs are concepts that have been done before, just arranged a bit differently. Thats where a lot of the fun is for me.---Brian


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## Brian Rupnow

I just ordered the same Model Engineer magazine (reprint) that appears in the very first post. I may not build the Lynx myself, but dang, I've got to keep up with what you guys are doing!!!---Brian


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## Swifty

Brian, I'm with you about the look of the toothed belt, spoils it a little bit. However that's not stopping me from building one. Maybe a cover over the belt and top wheel will work.

Paul.


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## Brian Rupnow

Swifty--Take a look for posts showing the Hoglet engine. It has a perfect example of exposed pushrods and rocker arms. To some it may be a step backwards, but once I get my set of plans I may change the design of the belt driven camshaft to mimic that on the Hoglet.---And i will probably do the design in British Imperial, not metric.---Brian


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## Swifty

Brian, I can see where you are going with the design, a bit of a rehash and you can have pushrods. You Canadians have to let go of the imperial system, metric is so much easier.

Doubletop, did you mirror image your picture of the completed engine, or did you build it that way?

Paul.


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## Brian Rupnow

Swifty--Ah, the magic of 3D cad. I can design the engine in either metric or imperial---it makes no difference. The parts are modeled at 1:1. Where the truly fascinating part comes in is when I generate detail drawings. By simply changing a setting on my system I can have the dimensions printed in metric, or imperial, or even in both. I don't type in any of the dimensions. The math data is input into the part files when I create them, and the actual drawing is almost fully automated, and the software picks up the information for the dimensions from the math data I use when modeling the part to create the dimensions. I am an old dog, and worked fully in Imperial until I was about 26 years old, when suddenly the world tilted on its axis and Canada converted (what a laugh) to metric. I have used both systems ever since, but at heart I am still more comfortable with Imperial.


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## doubletop

gus said:


> Hi Pete,
> You are my hero/meister. When can we see video of running engine?
> Will be late next week to start turning the C.I. Liner. Will proceed step by step as per Best of Magazine. Paul Swifty is about to get started.
> 
> Would you be running with dry crankcase or lube oil topped up Crankcase?.




I found that the oil level self regulates once it gets below the level of the bearings the flow stops coming out of the nose and the crank counter balance dips low enough and is big enough to chuck the remainder around adequately.


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## doubletop

> I have no idea what is going on here? This is the !!!!!th attempt to embed the video I've tried all the tags, the video link comes up in the edit screen and then everything disappears after the save. Even text after the video


http://youtu.be/1BVOu0xfaPw

You'll just have to make do with this link

<iframe width="420" height="315" src="//www.youtube.com/embed/1BVOu0xfaPw" frameborder="0" allowfullscreen></iframe>

Pete


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## Brian Rupnow

I have what I think is a legitimate question. All of the video's I have seen of the Lynx engines running show it turning a propeller.  I don't see any sign of a flywheel. Does the propeller stand in for the flywheel? Will the engine run without the propeller on it? I know that when an engine turns a propeller, it puts a nice constant load on the engine that increases with engine RPM. Does the Lynx NEED this load to run smoothly and not falter or rattle? I absolutely KNOW that if I built an engine with a propeller on it, the first thing I would do after the engine started and the propeller became a blur, I would stick one of my appendages into the damned propeller!!!---Brian


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## Swifty

Swifty said:


> Doubletop, did you mirror image your picture of the completed engine, or did you build it that way?
> 
> Paul.



Sorry, I only just realised that the picture on the front of the magazine is mirror image. I must pay more attention to the drawings.


Paul.


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## doubletop

Brian

The drawings include a water jacket and flywheel. In my case I did the Bobcat twin as water cooled so went for the air cooled version this time.







Pete


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## Swifty

Gus, I've started to machine parts already, starting with the crankcase. Just thought that I would warn you that on the drawing, all lines wether they are profiles, hidden lines, bolt hole circle sizes etc are all drawn as solid lines. It can get confusing, so watch out.

Paul.


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## Swifty

Brian, I'm with you regarding the propeller, I will be making a flywheel to run the engine and probably buy a cheap prop for display purposes. I've made it to 62 years with all my fingers intact after a working life as a toolmaker and doing my fair share of press trials, I don't intend to run risks now.

Paul.


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## Jasonb

Brian, just for you this one is running the marine flywheel and water jacket cylinder.

[ame]https://www.youtube.com/watch?v=wTq0ogyTFEc[/ame]

Malcom originally just had number/letter manes for his engine, only changing to the big cat makes at a later daye so you may want to also search for NE15S (Nemett 15cc Single) though there are a few different spellings of Nemett.

One thing to bear in mind with the flywheel is that the Lynx and Bobcat are faster running engines than  say the Hoglet so a large dia flywheel will have a lot more innertia so throttle responce will be affected so a bit slow to change speed when you blip the throttle and at 7500rpm will put a lot of load on things and will need to be well balanced.

J


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## doubletop

Brian asked me what the terminal was doing on the video and how advance adjusted the rev range so much. It doesn't.

The PIC software is controlled by the PC and allows the advance curve to be set up on the fly, with the engine running, in one of two tables of 32 advance steps across the rev range. It also allows pulse width to be changed, a sofware adjustment of the hall sensor trigger point and some other minor parameters. In order to help do this I added a servo output to control the throttle to manage one of the variables not related to the ignition, thats what I was adjusting.


[ame]http://www.youtube.com/watch?feature=player_embedded&v=1BVOu0xfaPw[/ame]



Pete


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## ICEpeter

Jason,
 While watching your video, I noticed your use of a stainless steel corrugated exhaust pipe from the engine to your silencer. Could you be so kind and let me know the ID and OD of the corrugated pipe and where you obtained it from? I am looking for a source for this kind of piping. Thanks.

 Peter


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## Jasonb

Not my engine, but I have seen the stuff somewhere, wil rack my brains now until I remember

J

Edit, came back quicker than I thought

http://www.macgregor.co.uk/saito/exhausts.htm


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## ICEpeter

Thank you much, Jason

 Peter


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## gus

Looks like Gus is getting all the expert help to make the construction of Nemett-Lynx Engine a success!!!

Maestros .Thank You. This really a shot in the arm.


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## gus

Swifty said:


> Brian, I'm with you regarding the propeller, I will be making a flywheel to run the engine and probably buy a cheap prop for display purposes. I've made it to 62 years with all my fingers intact after a working life as a toolmaker and doing my fair share of press trials, I don't intend to run risks now.
> 
> Paul.




I am going for flywheels. No props. This engine is too big.At this hp and speed , my fingers will shatter. Other than a left thumb which cannot bend fully,I have no desire to have my other fingers hurt.
I have to make up for mother's day and taking the darling boss for DimSum Lunch at the Sands Casino. No worry. I win everytime.That I do not gamble and so having not lost any money.I have won. Ha ha.
Gus not gambling. Its proven that Gus has no gambler's good luck.


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## Swifty

I'm with you on the gambling Gus, I'm just not lucky, I lose my money every time. I don't mind playing a couple of dollars but that is where it ends.

Paul.


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## gus

Not a productive day. Friend called. And its ransom. He wants his fishing rod repaired soonest and that is tonite. If not,he will not fix my Bait Cast Reels now with him. Spent two precious hours to replace line guides and expoxy coat bindings. :wall:

For today,all that is done is the cut length of Cast Iron Bar for the liner. Band saw came in handy to cut C.I.Bar. :hDe:
I have two hours only to turn liner with a lunch appointment at 11:30am.

Will plan and write work instructions to turn liner.


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## Brian Rupnow

Gus--I share your regard for your fingers. Mine are old and arthritic, and one has been removed with an axe  and then re-attached in the ancient past. However, I love them all dearly, and have no desire to part with any of them.--No propellers for this kid!!!----Brian


----------



## gus

Brian Rupnow said:


> Gus--I share your regard for your fingers. Mine are old and arthritic, and one has been removed with an axe  and then re-attached in the ancient past. However, I love them all dearly, and have no desire to part with any of them.--No propellers for this kid!!!----Brian



Hi Brian,

Looks like we have a unanimous vote----------"No Props. We want our fingers
intact."  My worries is ,in the process of trouble shooting the cause of engine problem and being deeply engrossed(will not rule out absent mindedness or just plain forgot we have a finger eating prop waiting"),we may lose our fingers or even hand. I have surplus off-cut C.I. Bars to cut flywheel. Or perhaps but a Brass Disc. (Not heard or seen posts from Canadian HP)


----------



## gus

OK. Got rid of all distractions. C.I. liner done. Took 4  solid hours. Being a big mini lathe and deeper cuts would stall motor.
O.D. is spot on. I.D. is 1/2 thou over. The parting off was scary. 4 hours of work could vanish in seconds.
I owe it Tin Falcon for recommending the Warner HSS Insert Boring Bar. No chatter.  
CI bar was too big,had to reverse jaws to chuck and tail stock centre to secure job. DIY Fixed Steady mobilised to secure over hung bar for drilling and boring. Parting off was between life and death of completed liner.
Will work on Cylinder Jacket tomorrow. Now working on works instructions to turn jacket.


----------



## gus

Been a productive day. Started work at 8am, took tea/pee breaks and worked till 1:30pm to complete.
Stretched the chuck capacity,with reversed jaws to clamp aluminium bar. Cutting the grooves and fins was nail biting.
Tapmatic Tapping Fluid made life easier with good flow of swarfs.
Will make drilling jig to drill all holes.


----------



## Swifty

That's looking great Gus, I hope my cast iron arrives tomorrow so I can work on it. The only work I've done today is cut some material for the back cover of the crankcase.

Paul.


----------



## gus

Hi Paul,

Found an error.
Cylinder Jacket.
Bottom flange O.D. 55 mm and 6 off 4mm hole with PCD of 50 mm will place Socket Head Allen Screws sticking outside flange.
Corrected to 47 PCD. 48 may be best. Checked Best of ME front cover found fasteners well centred.

Will work on the outer-head tomorrow. See no errors for now.
Bought XL 12mm mill today. "Totem'' Carbide Mill made in India.Will work on crankcase this Friday. Having fun cutting the grooves and fins but scary.


----------



## Swifty

Hi Gus, I hate to be the bearer of bad news and upset your evening, but the bottom flange is 60mm dia, the same as the rest of the cylinder. The 55mm dia is to the bottom of the first few grooves at the top. My M4 screws have a head dia of 7mm, this would mean the screw heads would nearly fill up the step completely. You may be able to machine a bit more off the 40mm recess dia to give some clearance. If you use 48PCD for the holes, plus 7mm head dia, this will make the outside of the screw heads 55mm dia.the same as your flange. You may have to taper the last few fins in order to get a screw and hex key in. I did mention in an earlier post that all lines are drawn solid, this makes it very confusing.

Paul.


----------



## gus

Swifty said:


> Hi Gus, I hate to be the bearer of bad news and upset your evening, but the bottom flange is 60mm dia, the same as the rest of the cylinder. The 55mm dia is to the bottom of the first few grooves at the top. My M4 screws have a head dia of 7mm, this would mean the screw heads would nearly fill up the step completely. You may be able to machine a bit more off the 40mm recess dia to give some clearance. If you use 48PCD for the holes, plus 7mm head dia, this will make the outside of the screw heads 55mm dia.the same as your flange. You may have to taper the last few fins in order to get a screw and hex key in. I did mention in an earlier post that all lines are drawn solid, this makes it very confusing.
> 
> Paul.



Will use studs and nuts and a yarn to spin later. ( To spin a yarn is Boy Scout language--------story to tell). No wonder the drilling jig shown in Best of M.E. was as wide as the crankcase top. OK . No problem. My drill jig will be made to  60 mm O.D. 
The Outer-Head looks tricky to cut. Will cut the blank Head and work out details.
Am happy with good progress and work pieces. No rejects so far.


----------



## Brian Rupnow

Gus--You are doing nice work. I am watching. Don't feel bad. I am currently modeling the Jaguar from Malcolm Stride's drawings, and I find his drawings confusing to read.----Brian


----------



## Jasonb

Gus you won't be able to turn the nuts. M4 nuts are 7mm A/F and you only have 3.5mm clearance between the cylinder and centre of the hole


----------



## Brian Rupnow

Gus--Can you do this to save your cylinder??---Brian


----------



## Jasonb

Or just skim down the 40mm dia waist by 1mm then you can fit the intended socket head screws.

Can't see how that ring will fit over the flange Brian ?


----------



## Brian Rupnow

Jasonb said:


> Or just skim down the 40mm dia waist by 1mm then you can fit the intended socket head screws.
> 
> Can't see how that ring will fit over the flange Brian ?


Split ring


----------



## mu38&Bg#

Consider a smaller screw. 6 M4 screws is excessive. Model aircraft engines use 4 M4 in displacements up to 2.2ci making considerably more power than this engine.

Greg


----------



## Niels Abildgaard

The latest Citroen 2 Cv engines had 74 mm bore cylinders that was kept  together with crankcase by three m8 (m10?) tie rods.
It is probably more than sufficient for put-putting model engines to have four cylinderbolts (not to short please) or tie rods that are one tenths of the cylinder diameter.


----------



## gus

Thanks for helping. Was nearly unforgivable goof and so many friends to the rescue. Long live ''HMEM''.
About to move on to the machine the Outer-Head which is mind boggling. Took the issues to bed. However I did get some sleep.

Lesson learnt.Read plans and ask questions.  Guess I am improving. ''Measure twice before cutting.drilling.turning etc etc.''


----------



## gus

OK .Took 3 1/2 hours to cut Outer-Head Blank. Cutting fins is scary. The O/H has some very difficult details to drill,mill,counter-bore etc.
Even more difficult for Gus w/o DRO. There will be at least three----five drilling jigs to make in order to get holes right. I am worried with the details on the holes for the valves. W/o DRO this will be tough and so back to WW-1 Workshop Technology.

Malcom's work instructions are very useful.Best to follow 100%. Cutting a spigot to chuck raw blank was a very good idea but to play
safe,I had tail stock centre snugged on to ensure blank does not fall out especially cutting fins which foul and cause job to fly out.
Parting-off was very scary. Saw out the last 1/2 inch.
Had to use the Height Gage to mark outer-head thickness. Note Gus's poor man's surface plate.

I am a nut on buy tools ahead of time. To drill and counterbore the valve ports made easy with spotting drills to spot on hole. Bought 2mm end mills ages ago. Use same to cut Outer head fins. Was nail biting.
See fotos. Since I have no DROs drill stops sure helped ensure required Couterbore depth.

5:30pm.
Made drilling jig to drill Outer-Head. WW-1 Technology still in use.


----------



## Jasonb

Gus I measured the heads on some M4 cap head screws last night and they were just under 7mm so you may just be able to use them without having to resort to other methods to hold the cylinder on. As you have not drilled the holes yet I would move them out to to a 47.5mm PCD which will place them in the middle of the flange and give the screw heads a bit of clearance to the 40mm waist.

Drawings show the head at 28.75, not whats on your height gauge.


----------



## Swifty

Gus, I would do as you mentioned in an earlier post, use a 48mm PCD for the holes, allowing for the 7mm dia screw heads, the smallest size across the screw heads will be 41mm, this gives you 0.5mm clearance per side. The outside size across the screw heads will be 55mm, the same as the outside dia of the cylinder. The screws won't hang over the outside and it will look OK.

Paul.


----------



## gus

Jasonb said:


> Gus I measured the heads on some M4 cap head screws last night and they were just under 7mm so you may just be able to use them without having to resort to other methods to hold the cylinder on. As you have not drilled the holes yet I would move them out to to a 47.5mm PCD which will place them in the middle of the flange and give the screw heads a bit of clearance to the 40mm waist.
> 
> Drawings show the head at 28.75, not whats on your height gauge.



Thanks for the alert.
I must change my specs. Where did I get 28.50?  Looks like will have to make adjustment somewhere to makeup. I have surplus to cut one more Outer-head if necessary.

I thought I had 28.75 but somehow it became 28.5 after my wife in to admire the Outer-Head.


----------



## Brian Rupnow

Gus---If you HAVE TO do it---You wouldn't be the first person to turn the heads down a few thou. in diameter on socket head cap-screws.---Brian


----------



## Swifty

For the home hobbyist, modifiying screw heads would be OK as a last resort. When I had a toolroom, anybody who attempted to modify a standard screw was told in no uncertain terms that it was not on, it makes maintenance a real pain.

Paul.


----------



## gus

Hi Brian,Paul.

When I was building Production Machines,I sure hate to introduce or do non-standard stuff. The Indian Ingersoll-Rand Air Compressors came in with different A/F Hex bolts that require 2  AF Spanners to loosen. They were not to SAE and not Grade 5. Was a nightmare.

Just rechecked,Think I get away w/o turning socket heads.


----------



## Jasonb

If it is a bit tight the ones with the smooth heads are a usually fraction smaller than the ones with the straight knurl around the edge


----------



## gus

There is so much details on the Outerhead and machining never seems to end and have O/H totally done.:wall:
At least,I did not wreck O/H with the last cut.
For this week, that's all Gus will do. Its weekend fishhhhhhiiing.
Next week cut the inclined face to take spark plug, the inlet and exhaust ports.


----------



## Brian Rupnow

Guys--We are not building production machinery here. It will probably never have to be maintained in our lifetime. If turning a screw head saves a part which has a lot of work put into it, then go for it. I'm not a novice in the industrial arts. This has been my life for half a century. I KNOW that anyone who used a non standard or modified fastener would be staked out on an ant hill and left to die by the head of engineering!!  But come on---It's a model for Gods sake. In model building you do whatever you have to do, and the only person you have to be responsible to is you.---Brian


----------



## Swifty

I also mentioned that it is OK for the home hobbyist, just threw the other bit in for general interest.

Paul.


----------



## doubletop

gus said:


> Thanks for the alert.
> I have surplus to cut one more Outer-head if necessary.



So hang on to it for now. I ended up doing two heads. However, at the point I knew I'd have to start again I kept going on the first one to prove all my setups and approach without worrying too much if I stuffed it up. The second one was way faster to make as I wasn't freaking out worrying if I was doing it the right way.

Pete


----------



## doubletop

Brian Rupnow said:


> Guys--We are not building production machinery here. It will probably never have to be maintained in our lifetime. If turning a screw head saves a part which has a lot of work put into it, then go for it. I'm not a novice in the industrial arts. This has been my life for half a century. I KNOW that anyone who used a non standard or modified fastener would be staked out on an ant hill and left to die by the head of engineering!!  But come on---It's a model for Gods sake. In model building you do whatever you have to do, and the only person you have to be responsible to is you.---Brian



I'm with Brian on this. We started this thread with a debate on fits. If it fits (properly)  its the right size. It not like you are making a batch and all the parts need to be interchangeable. If something breaks you aren't going down to the stores for a new one, you are going to make it yourself, so it fits....

Pete


----------



## Brian Rupnow

Whoops!!!  Didn't mean to start any kind of peeing contest here. I respect Swifty and think he is a super craftsman. (after all, he did build my engine). Us old farts who have worked around machinery all our lives know there are some things that you just DON'T DO. We also know that we have a lot more leeway on model engines that are in all respects "One offs" and probably will never require maintenance in the way real industrial parts do.----Brian


----------



## capin

Gus, it might have been a pain to do but You have got it licked now. I also have this on my list to do. Your doing great job!  Brian


----------



## gus

I just made a brand new paper weight. Cut the wrong side. Three days of hard work gone down the drain.:wall::hDe:
On the brighter side the next O/H will be best piece after a practice run.

May 20th 5pm.
OK . No more paper weight. Took my hobby problem to bed. 
Outer-head reworked. Put in a locktited plug spark plug hole. New hole for spark plug. 
Prefer to use Champion 10mm plug so as to standardise on plug. Fuel/air intake port and exhaust port to done later.

It's fishiiiiiiing tomorrow. 
Day after will start work on crankcase.


----------



## Swifty

That's a bummer Gus, it doesn't help either when they mirror image the picture on the front of the magazine, very confusing. Just noticed that I left out a tapped hole on my crankcase, the one for the belt idler, but that's an easy fix.

Paul.


----------



## gus

Swifty said:


> That's a bummer Gus, it doesn't help either when they mirror image the picture on the front of the magazine, very confusing. Just noticed that I left out a tapped hole on my crankcase, the one for the belt idler, but that's an easy fix.
> 
> Paul.



Hi Paul,
I just discovered the reversed mirror image foto. 
Believe I can save the out-head by plugging up the spark plug hole. But also debating making a new piece. 

Good luck with the other parts.


----------



## gus

Was able to cut the 25 degrees bevel corner of outer-head. The DIY arbor and bought out slitting saw from ArcEuro came in very handy and beats end milling. The Electronic Device to set angle certainly helped. Surprise.Surprise. Made in Singapore.Bought it year ago.Cost me a bomb. Checked accuracy on a 45 degree Set Square.


----------



## gus

Started work on the crankcase. The Vertical DIY BandSaw is an asset.If not,Gus would be panting away cutting the 2 1/2 '' square blank.
Facing the blank and milling the sides was man's job for a baby lathe and mill. At last the cylinder and outer-head have a crankcase to stand on. For smooth finishing,always use a new end mill.
Come tomorrow the crankcase cavity gets done. More like a tunnelling job from Singapore to reach Paul in Australia. Too much metal to remove.
Not fishing tomorrow as the ebb tide current brings little feeding fish and the rain today will kill all chances of landing good size fish.


----------



## doubletop

Gus

You are going well there. As per the write up drill the corners, bore the two large holes and then there's very little left to remove with the mill. I used a T slot cutter and was amazed how quickly it all came out. I subbed out the block for the Bobcat to a mate with CNC and it took him six hours to do the crank case. I think start to finish this one only took me about 4hrs

Pete


----------



## gus

doubletop said:


> Gus
> 
> You are going well there. As per the write up drill the corners, bore the two large holes and then there's very little left to remove with the mill. I used a T slot cutter and was amazed how quickly it all came out. I subbed out the block for the Bobcat to a mate with CNC and it took him six hours to do the crank case. I think start to finish this one only took me about 4hrs
> 
> Pete


 
Hi Pete,
Thanks for standing by me. Just the cavity took total of 8 hours. Using tee slot mill did not come into my head though I did use it for the Rotary Table Slots. The mini mill had to be coaxed to do the excavation.Am sure glad I did not destroy it with the last cut. Took lotsa tea breaks and pee breaks to recuperate.


----------



## gus

Excavating the crankcase cavity was a very tedious job with the fear of destroying job with last cuts of the day.
Did not dawn on me to use two fluke end mills. Was using 4-f mills and quill cuts with table hand feed.Cavity cutting took total of 8 hours.The quill feed max out at 10 mm depth. The depth of cavity was hard to gauge.DIY a mini slip gage and adjusted quill
for the cut. Turned out to be OK.
 Had to stretch & coax the Sakai,Japan Mill to cut crankcase. Would be great if I still have the BridgePort Mill,Leblonde 12 " Swing Precision Lathe and a big machineshop.Have to adjust and live with mini lathe and mill in a balcony shop.:rant:


----------



## Swifty

You've done very well Gus, all the big parts are nearly done.

Paul.


----------



## gus

Swifty said:


> You've done very well Gus, all the big parts are nearly done.
> 
> Paul.



The crankcase milling was nail biting. One excessive feed,the crankcase gone.
Trying get a crankcase wall finishing as good as yours was just impossible.
Foto shows Cylinder jacket bolted on to crankcase. Outer-Head has yet to drilled/tapped. Am wary of the orientation.Will be next week but I have two days off to do some deep sea fishing.
Bearings bought. Will be working on the bearing housing.


----------



## Brian Rupnow

Looks awesome Gus!!!---Brian


----------



## gus

Brian Rupnow said:


> Looks awesome Gus!!!---Brian




Thanks Brian for the support.

Off fishing this Sunday.Darling Boss wants fish.


----------



## gus

World War 1 MachineShop Technology.

With no DRO and the Rotary Table has yet to be graduated in Degrees. Drilling the bolt holes for the cylinder jacket and outer-head falls back to WW-1 methods---------drill jigs and fixtures. The humble divider to scribe pitch circle and divide holes.
Even my tapping is WW-1 too. Tapmatic Fluid sure helped reduce the friction and gives good shiny thread. About time to DIY an Auto Tapping Machine. Suggestions ,Please.


----------



## gus

Spent entire morning drilling and tapping M2.5,M3,M4,M5 and M6 Holes. All in 22 drilled/tapped holes. Engine supports done but deviated from print. Used 15mm Angle bought from TokyuHands months ago.Crankcase cover done but beefed up to M6 overflow port.
Cylinder Jacket.
See foto. Believed Malcom did same. See shortened Allen Key to fit in.
Decided to use CM6 Spark Plug instead of the humongous Champion Plug.
Outerhead still some details to finish up and from there on to the bearing housing .

Not a very productive morning in terms of number of parts done. But number of parts count is now 7.


----------



## Swifty

Gus, it's coming together nicely, that plug does look better than the other one that you had, the size is more suitable. I have just about finished all my larger parts now, so will be working on the small bits next.

Paul.


----------



## gus

Swifty said:


> Gus, it's coming together nicely, that plug does look better than the other one that you had, the size is more suitable. I have just about finished all my larger parts now, so will be working on the small bits next.
> 
> Paul.



Hi Paul,
Gus had a productive day with nothing for the ''Rag & Bone'' Man. Part count only -----------one.
Took my time to turn the bearing housing and it was 4 hours just the unbored blank. The taper part was done by hand and hence a bit rough but the 1000 grit
Emory Paper did a good job improving the finishing.The Bearing Housing Spigot done with a push fit into crankcase. One bearing went in with push fit.
The front bearing bore will be done tomorrow.Cutting Tools are HSS. No Carbide.
Crankcase now all covered up.
Internal parts will be done from next week. Pretty lot of parts to do and some have unforgiving fits.


----------



## doubletop

Gus

You are going well there. A nice steady productive pace.

Pete


----------



## Swifty

Gus, your doing a great job, you are certainly an inspiration to those with smaller machines and limited work space.

Paul.


----------



## gus

Got out of the rework mess I created for myself. Counter bore for Mini CM6 plug done so socket spanner can be used to tighten/loosen plug.Can now go after the misc. parts.
 Intake and exhaust ports done. 
Main shaft done except crank disc.M8 thread done with DIY Thread Die. Somehow the modern thread dies give us well form/cut threads. Shaft material was Grade 5 Hex Bolt which can be hard to thread die.Whereas in Trade School,all we got was very bad threads with the dies drawn from tool room. The taps were not any better and tends to break in our trade school projects.Can only guess they were badly worned.
Next week will see more and more parts turned out.


----------



## Brian Rupnow

Gus--that is looking really good.---Brian


----------



## Swifty

Gus, I counter bored my cylinder head today to suit the 1/4x32 plug that I bought, although I think that your 10mm thread plug may be a better size. I can always change later on.

Paul.


----------



## gus

Swifty said:


> Gus, I counter bored my cylinder head today to suit the 1/4x32 plug that I bought, although I think that your 10mm thread plug may be a better size. I can always change later on.
> 
> Paul.



Hi Paul.

Please be cautious. Malcom's dimensions etc are very tight and not much room to mess with. Felt like kicking myself for getting out of line.That's my nature-----going against convention. For a while I thought the Outer-Head would be a goner.:wall:Used a modified fly-cutter to counter-bore.Had earlier skimmed down 14 mm socket spanner to fit. But later found a Taiwanese Spark Plug Spanner that I could not resist. We can compare engine performance i.e. 1/4'' v/s 10 mm. Very much relieved the O/Head
was not ruined.In fact from ugly darkling to ''Swan'' 

Looking for tools nowadays is so convenient with the ToolMaker's Chest and Tool Cabinet.
No longer hunting high and low.


----------



## GailInNM

Looking really nice Gus.
Gail in NM


----------



## Swifty

Gus, I think that your engine making ability is coming along great, when you are able to recover from mistakes, change the plans to suit yourself etc, it shows that you are more confident in what you are doing and your abilities are increasing.

Paul.


----------



## gus

Swifty said:


> Gus, I think that your engine making ability is coming along great, when you are able to recover from mistakes, change the plans to suit yourself etc, it shows that you are more confident in what you are doing and your abilities are increasing.
> 
> Paul.



Thanks , Paul.

I tend to misread plans. The Cylinder jackets fins ended up as 5 mm deep/high but should be 2 1/2mm. The bearing housing ended with 7 holes instead of 8.How did I miscount. Hopefully Gus will improve with the next engine with zero goofs.The next engine would be the Jaguar but I prefer the Australian Model Engineering Magazine Jan/Feb 2013 version with fabricated crankcase. This will be in 2015. Two engines per year ,I get burnt-out.
Next week will be exciting. No distractions other than the R.C. Church repairs
with breakers going on and on. By mid June it will reopen for Sunday Mass.
Meanwhile mass is said in the canteen which I  dread.


----------



## gus

CrankDisc done but some mishap happened. The return scroll spring for the quill broke after 10 years of faithful service.:wall:
Sure hate to give to the ''Rag n Bone Man'' who is sure to tear it pieces.Nobody would want to buy a broken down drill press. Did a ''Bush Engineering'' repair. Looks like Gus just won't dump the drill press after all. A bit of improvement will make m/c look great and unusual.th_wav

The parting off 50 mm CrankDisc was nail biting,took my time with plenty of Tapmatic dobs and tool withdrawal to clear chips.
Cutting the profile with the Bandsaw was labour savings. Cut on next close the marked lines and clean up with some filing.
Will do crankpin tomorrow.


----------



## gus

The Cam-Box looked very simple make but to my surprise ,I spent entire morning from 8-----12 noon plus another 2 more hours
to drill&tap and mount on outer-head. Must put table stops so as to avoid overshot cuts. Had to rework and skim with 6 mm roughing mill to trim to satisfaction.
There is a mountain high of mini parts to machine. Other than rant/dread,I might as well enjoy doing every part and make them good looking.


----------



## Brian Rupnow

Gus--I am always surprised how a person can breeze through all of the big engine parts with a fairly low degree of frustration, and at the end of a day have something really impressive to look at. When you get into all of the "fiddly bits" one can work all day, and at the end of the day have a surprisingly small pile of very unsophisticated little parts that makes you think "Gee---Is that all I done today??"---Brian


----------



## doubletop

Looking good Gus. The way you are going you'll get through those fiddly bits OK. The cams and valves are going to be interesting on your setup so spend a bit of time thinking about how you plan to tackle them accurately. Them and the fit of the piston are most important parts of the job.   Pete


----------



## gus

doubletop said:


> Looking good Gus. The way you are going you'll get through those fiddly bits OK. The cams and valves are going to be interesting on your setup so spend a bit of time thinking about how you plan to tackle them accurately. Them and the fit of the piston are most important parts of the job.   Pete




Hi Peter,

Thanks for the tip.
By now done two pistons for Webster and Rupnow and they were OK.
But I have no piston rings making experience. This is where I fear to tread.
The cams are so mini. This another fear. I am watching Paul Swifty doing these.Will monkey see, monkey do.


----------



## gus

Disaster struck today at 4:30 pm. After 14 years of drilling and tapping,I broke a tap and it just has to be a M3 Tap and of all the time to happen. Beyond extraction. 
So move on and make another cam box.Lesson learnt---------dump M2,M3,M4 taps after 2 years service.M3 and M4 is frequently used.


----------



## Swifty

That's a shame Gus, but it's only a small part and easily replaced. You will make the next one in half the time. I'm already feeling nervous about making the piston rings, I think that I'm worried that I may split them when putting them on the piston, I better make a few spares straight away.

Paul.


----------



## Brian Rupnow

Gus--Make up a solution of Alum salts dissolved in water--as much as you can get to dissolve in it, Put in plastic container and soak aluminum part in it overnight. Keep the solution as warm as you are able without melting the plastic container. Overnight it will dissolve the tap and not hurt the aluminum.---Brian


----------



## gus

Swifty said:


> That's a shame Gus, but it's only a small part and easily replaced. You will make the next one in half the time. I'm already feeling nervous about making the piston rings, I think that I'm worried that I may split them when putting them on the piston, I better make a few spares straight away.
> 
> Paul.



Will need your good advice to make piston rings. Will make a couple more for insurance. The pistons I bought for Webbie and Rupnow engines were quite tough.
We did break some 15mm O.D. piston rings while repairing a 5000 psig compressor.


----------



## gus

Brian Rupnow said:


> Gus--Make up a solution of Alum salts dissolved in water--as much as you can get to dissolve in it, Put in plastic container and soak aluminum part in it overnight. Keep the solution as warm as you are able without melting the plastic container. Overnight it will dissolve the tap and not hurt the aluminum.---Brian




Good advice but Alum is a controlled chemical in Singapore. Need license to buy. I have just finished a blank. Will take about 2 hours to make replacement.
I have moved on.


----------



## gus

Took only 2 1/2 hours to make new Cam-Box but the fitting up wasn't done till 5pm. The slot hole is better looking than the last one. Cam shaft,shaft bearings,breather cap screw etc mounted on Outer-Head.


----------



## doubletop

Guys  Don't stress about the rings. You've made the liner Ok and you've cut the fins in the head just combine the two processes and you'll kick yourself how easy the rings are. Breaking them is also easier than you think.  I had similar concerns, made the rings to size and parted of 16 of them. Heat treated and gapped 8 and used 2. The rest are spares that will last somebody about 50 years if not longer.  Follow Malcolms write up, including the heat treatment jig and you'll be fine.  Pete


----------



## gus

doubletop said:


> Guys  Don't stress about the rings. You've made the liner Ok and you've cut the fins in the head just combine the two processes and you'll kick yourself how easy the rings are. Breaking them is also easier than you think.  I had similar concerns, made the rings to size and parted of 16 of them. Heat treated and gapped 8 and used 2. The rest are spares that will last somebody about 50 years if not longer.  Follow Malcolms write up, including the heat treatment jig and you'll be fine.  Pete



Thanks. Peter.

The sub-contract turner who made 3/4'' pistons for our high pressure compressors died five years ago. Just wish he is still around. 

OK. Read,comprehend and download into my brains Malcom's method.

In about two weeks will make the P.Rings. Will be fun. Malcom has lotsa surprises for us. By the time we complete and run the Nemett-Lynx Engine,
hopefully Gus becomes 3/4 or fully baked in 4 stroke I.C. Petrol Engines.
Plan to build the Jaguar too.


----------



## Brian Rupnow

Gus--You're right---The cams are very mini. I just checked, and the cam for the Lynx is almost identical to the Jaguar engine. I just made my cams today, and after a bit of hassle they turned out okay, but my goodness, they are small. I suggest you have a read through my post before you start to machine the cams.---Brian


----------



## gus

Brian Rupnow said:


> Gus--You're right---The cams are very mini. I just checked, and the cam for the Lynx is almost identical to the Jaguar engine. I just made my cams today, and after a bit of hassle they turned out okay, but my goodness, they are small. I suggest you have a read through my post before you start to machine the cams.---Brian



Hi Brian,

Thanks. Will monkey see.Monkey do.

Paul succeeded making good looking piston rings.Piston ring making now no longer a black magic art.

My fishy mates decided to take a break to take their '' better halfs'' for Saturday Brunch. Spent whole day cutting/milling the tiiming case and disc. Profiling the Timing Case made possible with the DIY  Rotary Table which is not quite completed. Some improvements required to done to take off the back-lash.
Crankshaft keyed with 3 M3 fasteners. Crankshaft now fittted in with a dummy prop chuck. CrankPin Needle Bearings just came in from ArcEuro. Con-Rod and pistons will be next to do.


----------



## Swifty

It's all going well Gus, I'm just about finished with the bottom half on mine, now working my way towards the top. I will probably work on the valves next.

Paul.


----------



## gus

Swifty said:


> It's all going well Gus, I'm just about finished with the bottom half on mine, now working my way towards the top. I will probably work on the valves next.
> 
> Paul.



Needle Bearings just arrived. Next week will be con-rod and piston. Followed by piston rings. Probably valves the week after. The cams will be fun. For now the cams maybe Webster and Rupnow type. I have no DRO. Cutting the cams the ''Malcom'' way just unthinkable w/o DROs. Will cross the bridge when I come to them. Neap Tide tomorrow.Will try the 70' deep rocky structures where good size Groupers lurk. Will be losing fish,line and sinkers. Success means big fish.


----------



## gus

The DIY Harold Hall Boring Head was meant to bore holes from 3/4------1 1/2'' I.D.  The Con-Rod big end ''14 mm O.D. needle bearing'' means BH must be modified to bore this I.D. Spent 3 hours   brain-storming and came up with ''add on'' adapter. No ''Bush Engineering''.
Trial bore was a success.  Will mark out material for Con-Rod. This time will use Height Gage to mark 58.25 mm center-distance on Con-Rod.


----------



## gus

The Con-Rod took time to do. After two days ugrading Boring Head to bore 14mm I.D. Big plus one day(today) make fixture to profile big end and small end of Con-Rod. Will be tomorrow to complete.The Con-Rod required to fixtures.One to bore and the other to profile.


----------



## gus

The Con-Rod looks very simple but with my WW-1 Workshop Technology, it will be very basis skills. Jigs and fixtures required to finish up Con-Rod. 
The crankshaft now have a Con-Rod to spin. Made DIY bushing for the big end needle bearing.Quite happy with the fit.Material was Grade 5 Hex Bolt. 
Took three days to come this far.:rant:


----------



## Swifty

It's coming along nicely Gus, no work on mine today as we had friends over for most of the day, the friend was my foreman when I had a toolroom, a very nice fellow.

Paul.


----------



## gus

Swifty said:


> It's coming along nicely Gus, no work on mine today as we had friends over for most of the day, the friend was my foreman when I had a toolroom, a very nice fellow.
> 
> Paul.




Will be good to take a break to avoid burnt-outs. After finishing touches to the con-rod and crankshaft,will cut the piston. Then figure out cutting the piston rings and make the heat treatment tooling. I have Mapp Gas Torches.
Will be fun.


----------



## gus

Simple looking aluminium piston took 3 hours to complete in the morning and another 2 hours to fit into crankcase and cylinder assembly. 

Honing done with brake drum cylinder hone and Makita Cordless drill.
At last the rotating and reciprocating portions done and Gus could spin the crankshaft with the piston moving up and down.Piston rings will get done tomorrow. And from here will be moving upwards into valves and cams.

Took darling boss out for Indonesian Medan Food. See food and piston in the cylinder sleeve.
We had Rendang Beef,Rendang Chicken, Soto Ayam Soup and Deep Fried Pork Belly.Good eating but health hazard.


----------



## BaronJ

Hi Gus,

Coming along nicely !  I have one of those hones.  Where do you get your spare stones from.  The ones supplied with mine didn't last ten minutes.  They wore away at one end despite being full in the bore.

I got another wiper motor this morning.  Getting on with MK2 !


----------



## Swifty

Baron, you might have difficulty getting replacement stones, the hones are virtually a throw away item. Despite this, you could try any good Toolmakers supply shop, they should have a good range of polishing stones, usually in 6" lengths.

Paul.


----------



## gus

Had to make new con-rod. After fitting in con-rod with piston on to the crankshaft into crankcase, I had difficulty cranking over.
During the process of pressing in needle bearing on to big end,same got mis-aligned and would respond to re-alignement.
Make new rod. Four jaw chuck did not have the capacity to hold off-set rod blank. Tried a very odd way of job holding with the three jaw chuck.Surprise.Surprise.It worked. Re-discover I could reduce blank thickness by turning on the lathe and much faster than end milling.


----------



## bmac2

Hi Gus. 
Was reading Swiftys build and you had said you had no way of measuring accurately on the Z axis on your mill. This is the cheap, quick and dirty method Ive been using on my mill almost since I got it home. Its just a clamp that fits on the column and holds a dial indicator. No fancy angles just cut to fit and bolted tougher out of whatever you have around. You should be able to rig up something so it can read off the quill. The bolt sticking out of the bottom is so I dont smash into the indicator when I move the head up. Best of all its dead accurate and . . . . . . . NO BATTERIES Thm:


----------



## gus

bmac2 said:


> Hi Gus.
> Was reading Swiftys build and you had said you had no way of measuring accurately on the Z axis on your mill. This is the cheap, quick and dirty method Ive been using on my mill almost since I got it home. Its just a clamp that fits on the column and holds a dial indicator. No fancy angles just cut to fit and bolted tougher out of whatever you have around. You should be able to rig up something so it can read off the quill. The bolt sticking out of the bottom is so I dont smash into the indicator when I move the head up. Best of all its dead accurate and . . . . . . . NO BATTERIES Thm:




Great idea. But have modify to suit round column pillar.


----------



## gus

The Timing Gears and belts came in. Will be busy over next two weeks. But I thought I am taking my sweet time so why rush.
Hi Paul.
Its fishing time today. Not too bad but I lost three with 20 lb line breaking off. This gentleman nearly had a heart attack with this
Diamond Trevally.Fishing again tomorrow.


----------



## BaronJ

Swifty said:


> Baron, you might have difficulty getting replacement stones, the hones are virtually a throw away item. Despite this, you could try any good Toolmakers supply shop, they should have a good range of polishing stones, usually in 6" lengths.
> 
> Paul.



Hi Paul,

That is what I suspected may be the case.  I don't think the ones that I bought were very good at all !

Your right its in the scrap bin they go...

Thanks:


----------



## BaronJ

Hi Gus,

Very pretty !  I mean the engine, not the fish


----------



## gus

Timing Gears bored,reamed and mounted. Spacers on Crankshaft done. Will assemble tomorrow into Bearing Housing.
New Con-Rod done. No more obstruction when I crank shaft and piston.
Gus down with a very mild flu.Recovering fast.No worry.


----------



## BaronJ

gus said:


> Timing Gears bored,reamed and mounted. Spacers on Crankshaft done. Will assemble tomorrow into Bearing Housing.
> New Con-Rod done. No more obstruction when I crank shaft and piston.
> Gus down with a very mild flu.Recovering fast.No worry.



Sorry to hear that you're not so well.  A glass or three of the good stuff will help with that.  

That engine cylinder looks very mean with that lot up top.  I assume that is the drive for the camshaft.  Looking forward to seeing it running.


----------



## gus

BaronJ said:


> Sorry to hear that you're not so well.  A glass or three of the good stuff will help with that.
> 
> That engine cylinder looks very mean with that lot up top.  I assume that is the drive for the camshaft.  Looking forward to seeing it running.




Have a problem drinking. Not enough.I can't sleep. Just enough.I fall asleep and wake up at 3 am.Drink too much,I can't sleep.  But two glasses of Red works.
Will do that tonite.
Did some improvement on the idler pulley bolt. Machine a brass hex bolt to improve aesthetic.


Not a very productive morning in term of work quantum.
Just discovered how to fit in timing belt. Both have to be pulled together.

Timing system fitted in. ;D

Moving on to piston rings. Reading up now and jotting down work instructions and make sure I have the required tools/cutters to do a good job once and not two/three times.


----------



## gus

Breather line fittings done and figuring out how to connect and look good. May have to do it my way to make easy/direct/good looking. Been a long long not done control piping. I have a DIY tube bender made 10 years ago.

There are some forum members omitting the breather line which is required to oil cams,cam-shaft and tappets. Crankcase pulsation is just excessive and must be balanced out.


----------



## Swifty

Hi Gus, where did you get the fittings for the breather, are they a standard hydraulic fitting?
I assembled the rings to my piston tonight, and fitted it into the cylinder, lots of pressure when I cover the end with my hand.

Paul.


----------



## gus

Swifty said:


> Hi Gus, where did you get the fittings for the breather, are they a standard hydraulic fitting?
> I assembled the rings to my piston tonight, and fitted it into the cylinder, lots of pressure when I cover the end with my hand.
> 
> Paul.



They were DIY from samples but modified. The Cap-Nuts were 10mm Brass Hex with M8 and the nipple M5 make. I still had some olive sleeves left.
See fotos-------DIY tube end fittings and engine breather tubing done. Too many bends will redo my way with one clean bend. May be running short of olives. No Problem.DIY olives. Tube bender is also DIY.

Not happy with too many bends. Redo breather tube to 2 bends that is a big bend and small bend. Now breather tube looks plain and simple and was easy to bend with plenty of lee-way to play with and then lock on.



Lotsa pressure .Thats good and this is because piston/rings and cylinder seating
well.


----------



## gus

Well. The mild flu is about dead and gone and Gus still alive. Went on at 4 pm to cut piston rings.
Since I have 6------20 mm twist drills,bored ID with 6mm pilot hole and from with incremental of 2mm to 20 mm with 3 mm
to hit 23mm I.D.
See fotos. My first C.I. Ring. SWMBO boss just called,''Gus take a rest.''


Paul,
1. Were you using a MT3 shank to split rings. Looks like I have to buy or DIY same. 
2. Please advise OD of heat-treatment holding device. I am worried about deformation and ring
    OD gone oval.

Went out to buy 4 mm OD copper tubing and also to get my ''71' young system tuned up after
the flu.Good reason why I could cut one blank ring.


----------



## Swifty

Hi Gus, the redone breather tube looks great. I used a 3MT shank to split the rings, although you could turn up a tapered shaft to split them on, just polish the surface so there are no snags, I used some 1" OD copper tube to push the rings evenly. 

The heat treatment fixture had a diameter of 24mm to hold the rings open, this worked well, the rings fit really well. When I hold my palm over the cylinder and move the piston, there is lots of pressure.

Not much done the last couple of days, I just made the tensioner pully. I went flyfishing again today to the same place as last week, best I could do was to lose a fish when the fly broke off the line, I always check my knots carefully, but it broke anyway.

Paul.


----------



## gus

Good to take break and recharge batteries. SWMBO suggest I take a break from fishing to fully recover. No fishing this Saturday and Sunday.
Its Neap Tide and fish won't bite.S$45 Diesel x two days saved.
Will make the 3MT if I have the material.
Have a good fly-fishing trip.


----------



## gus

Best to use Malcom's method of mounting piston ring blanks on a no. 3 MT mandrel to split same.  I have no 3MT sleeve or shank. Made a short mandrel using recycled off-cuts. The mandrel really help give a clean break with little filing to finish up,
Made heat treatment clamp to clamp rings. The DIY rings turned out to be equivalent bought out piston rings.
Making and heat treating rings now no longer a black art.


----------



## BaronJ

gus said:


> They were DIY from samples but modified. The Cap-Nuts were 10mm Brass Hex with M8 and the nipple M5 make. I still had some olive sleeves left.
> See fotos-------DIY tube end fittings and engine breather tubing done. Too many bends will redo my way with one clean bend. May be running short of olives. No Problem.DIY olives. Tube bender is also DIY.
> 
> Not happy with too many bends. Redo breather tube to 2 bends that is a big bend and small bend. Now breather tube looks plain and simple and was easy to bend with plenty of lee-way to play with and then lock on.
> 
> 
> 
> Lotsa pressure .Thats good and this is because piston/rings and cylinder seating
> well.



Hi Gus,

It looks a lot better in that last picture.  It needed the elbow to make it look right.

Fine about your home brew bender !  It looks similar to one I made years ago when playing about with cars.  I no longer have it !  It got wet and went rusty.  It resides with the scrap man now, along with various other old tools that got a soaking in water.


----------



## tornitore45

I am collecting parts before starting and have problem sourcing:
The belt
The big end roller bearing sleeve.  As a cope out I see no problem here making the crank pin 10mm and harden it to fit directly the needles ID, unless someone see a problem.

Anyone can share a source? Preferably USA.


----------



## Swifty

I had no problem at my local bearing suppliers getting most things, the only part that they didn't have in stock was the inner sleeve for the big end bearing. They could have ordered one in easily enough, but I modified the design and used a hardened 10mm pin on the crank. The belt was supplied as a standard item from the place I ordered the wheels.

For the belt, just make sure that you are looking at mechanical transmission suppliers.

Paul.


----------



## tornitore45

> I modified the design and used a hardened 10mm pin on the crank.



He, he Great minds think alike.
In my search I dig up lots of UK and AU sources but spotty and incomplete stocking US side.
I guess is time for the US to take the last painful step to metricate the last 5% of the industry.


----------



## gus

tornitore45 said:


> I am collecting parts before starting and have problem sourcing:
> The belt
> The big end roller bearing sleeve.  As a cope out I see no problem here making the crank pin 10mm and harden it to fit directly the needles ID, unless someone see a problem.
> 
> Anyone can share a source? Preferably USA.



Hi Mauro,

Welcome to the Nemett-Lynx Engine building Team. It's been fun building this engine. Did get one sleepless night but woke up and chided myself,its not paid work and I won't get the sack. Went back to sleep. 
Tried to buy pistons from the usual USA vendor but they make only imperial size rings.Was forced to cut the rings using Malcom's method. I came up with 6 out of 7 rings. Making your own piston rings now no longer a black magic art. Next would the valves and the cams. Not difficullt if you religiously read and follow Malcom's Work Instructions.


----------



## gus

Valve guides done and pressed in. Tappetts done too. Valve will be fun and that will be next week. Not fishing tomorrow but will turn up to see my fisho friends bring in their catch.


----------



## gus

This is third set of DIY valves cut on the lathe. Left it unparted to use other end as lapping handle.
Also tried hand coiling valve springs. Scrapped first two springs to try out hand coiling. A very tight firm grip on SWG 20 wire is a must to get good spring forming.
Made two good springs 8 turn x 7 mm OD x 16 mm L. .

Will move on to cam cutting. Before doing so,some prepping required.
RT has no angle graduation and some form DRO or dial required.
Will be fun.To get good results,you need the tools and jigs etc etc.


----------



## doubletop

Mauro - try here http://www.beltingonline.com/ not the US but cheap and they ship

Pete


----------



## tornitore45

Thanks for the belt source.

I am not yet building the Lynx, just collecting the purchase parts and some missing metal stock, also scrutinizing the drawings to understand as all fit together.  I will probably "imperialize" the design a bit, where possible.

Presently building the Dulcos 6 strokes hit&miss but the Lynx is definitively next, is just too good looking an engine.


----------



## gus

tornitore45 said:


> Thanks for the belt source.
> 
> I am not yet building the Lynx, just collecting the purchase parts and some missing metal stock, also scrutinizing the drawings to understand as all fit together.  I will probably "imperialize" the design a bit, where possible.
> 
> Presently building the Dulcos 6 strokes hit&miss but the Lynx is definitively next, is just too good looking an engine.



Hi Mauro,

Malcom's dimensions, fastener sizes, drillled/tapped hole centre distances are very tight. A slight miss can mean clashing. I did have have some clashes when
I ventured off. The outer-head counterbore diameter must be exact.The cam box drilled holes can clash. I messed with the 1/4'' plug and went to 10 mm
CM6 was very unforgiving. Did my trade school in Imperial Units and took quite a while to go metric. Glad I did as Imperial Size fasteners are nearly non-existing in Singapore.


----------



## Swifty

Mauro, here is a link to a belt supplier in Texas. A google search of timing belts or synchronous belts will give you lots of suppliers.
http://www.bdi-usa.com/Locations.aspx?State=TX

Paul.


----------



## BaronJ

Hi Gus,

Getting on great with that engine !
Anyway here is my contribution to help with the RT calibration !
http://www.cgtk.co.uk/metalwork/divider
If you have a nosey round the site there is also one for linear scales.

HTH.


----------



## Brian Rupnow

Gus I truly do hope you are feeling better. Where are you at now on this engine?--I see over on Swifty's thread that you seem to be re-making many of the pieces. Have you made the cams yet? The cams are not terribly difficult, just time consuming, and you really do need a rotary table with degree markings and some form of digital readout on the quill advance. I have been so tied up on my build that I have lost track of where you are on your build. Mine is finished now so I will have to live through your build and Swifty's build.---Brian


----------



## gus

Brian Rupnow said:


> Gus I truly do hope you are feeling better. Where are you at now on this engine?--I see over on Swifty's thread that you seem to be re-making many of the pieces. Have you made the cams yet? The cams are not terribly difficult, just time consuming, and you really do need a rotary table with degree markings and some form of digital readout on the quill advance. I have been so tied up on my build that I have lost track of where you are on your build. Mine is finished now so I will have to live through your build and Swifty's build.---Brian




Hi Brian,

Made too many errors on the Outer-Head which is really a base for 4 sub-assemblies to mount on. Guess I am not familiar with CAD prints. Still in the 1960s of hand drawn drawings which easy to read and comprehend.
Having made so many errors,I have learnt good lessons and the second outer-head looks good and will take on the sub-assemblies. Now have the tools required for the job. Come tomorrow the Outer-head will be done.

Am glad I moved on.
Next week will see to new tools and accessories to tackle the cam milling.


----------



## gus

BaronJ said:


> Hi Gus,
> 
> Getting on great with that engine !
> Anyway here is my contribution to help with the RT calibration !
> http://www.cgtk.co.uk/metalwork/divider
> If you have a nosey round the site there is also one for linear scales.
> 
> HTH.




Hi Baron,

Thanks for the divider. Bought a protractor and mounted on the bottom with cheap n nasty indicator. See foto. Looks like cam cutting can proceed next week. Being a born loser/goofer(mistake prone,will read Malcom's Work Instructions many times to comprehend. The engraving carbide cutter has yet to arrive. Will proceed with protractor. Will trial cut one cam.


----------



## gus

Brian Rupnow said:


> Gus I truly do hope you are feeling better. Where are you at now on this engine?--I see over on Swifty's thread that you seem to be re-making many of the pieces. Have you made the cams yet? The cams are not terribly difficult, just time consuming, and you really do need a rotary table with degree markings and some form of digital readout on the quill advance. I have been so tied up on my build that I have lost track of where you are on your build. Mine is finished now so I will have to live through your build and Swifty's build.---Brian



Hi Brian,

RT with temporary protractor done. Foto attached.The cheap n nasty degree reader is not M.I.C. but M.I.S.(Made in Singapore) 
Now moving on to cook up a DRO tonite.
Thanks for the kind help and support. Gus is still a very green horn in engine
building but I am learning fast with two running engines under his belt and one more to come soon plus many more before I drop dead. Gus is 71 and counting his days one by one.Every day is a blessing and bonus.
Take care.


----------



## BaronJ

Hello Gus,

I think that is very inventive of you !  Well done.

Now as far as "Gus is 71 and counting his days one by one.  Every day is a blessing and bonus."  I'm not too far behind you.  I agree with every word.


----------



## gus

All righty. Gus should be back on his horse again. Here is the proof. My mental block --------the Foot Pedal Speed Controller is done and tuned and live tested with 110v Coffee Grinder which I mistakenly bought and not usable for Singapore's 230v supply.
This is the second attempt. The 110v----220v electronic speed controller got into stonewall surged and made fishing line spooling
of large baitcasting unstable. Spooling smaller reels was very good and stable but larger larger reels we had very unsteady spooling and breaks fishing lines. Hopefully Foot Pedal Speed Controller will past the line loading test tomorrow.
RT is done and calibrated. Number stamping was done with a jig.W/o same jig. there will be dancing numbers.
Some prepping to be done before cam cutting.


----------



## gus

Now moving on away from the two year old Foot-Pedal Speed Controller nightmare. Every fix I came up with last only six months with the M.I.C. Rheostats. The last electronic Speed Control Device went wacky .

With a mini mill it is just impossible to mount magnetic stand and dial gage as per Malcom's.My mini mill is not much bigger than the magnetic stand and dial set.See foto.
Been brain storming for a month. Here is my solution. Drill into mini mill's radial arm.Was very painful for Gus to mutilate mill. However the outcome looks good.

One last prep to do before cam cutting. The Centre Support which must be simple/good and fits on to the mill table.The Vertek Angle Plate bought in HongKong last year would help make simple Centre Support.


----------



## Brian Rupnow

Gus--Check your email and your junk folder. I sent you a drawing yesterday with all of the critical Lynx cam dimensions on it.---Brian


----------



## gus

Brian Rupnow said:


> Gus--Check your email and your junk folder. I sent you a drawing yesterday with all of the critical Lynx cam dimensions on it.---Brian




Hi Brian,

Thanks. 

Now working on the tail stock to steady/support cam blank.


----------



## BaronJ

Hi Gus,

Do you want a copy of my PWM speed controller circuit ?


----------



## gus

BaronJ said:


> Hi Gus,
> 
> Do you want a copy of my PWM speed controller circuit ?



Hi Baron ,

Thanks.

My E-address [email protected].


----------



## gus

Cam cutting will be done this week,now that the prep equipment is all done.
Took a bit of time to retrofit RT and graduated to read degrees on the top disc and handwheel dial. The Centre support took four days to come up and complete. Material came from scrap bin and left-overs. Centre is screw operated to forward and retract.
Now reading Malcom's work description and update with my gurus's work samples and tthread posts.
First trials can happen tomorrow and from there the real crankshaft.


----------



## gus

Cam cutting exercise went smoothly but still a learning curve. Dial gaging to mill cam did not work out. Needle was shaking all over and finally moved around like hour hand. Rigged up a ''Bush Engineered DRO"" which worked. First cam cutting continued.
Second practice run will happen tomorrow and hopefully from there the real steel cams appear.
The retrofitted RT performed well w/o rattling. The DIY Centre Support worked.
*Cam Cutting*
It is true , you can't teach an old dog new tricks. Malcom's cam cutting with the offset by the degree somehow puzzled me.After biindly following his method ,the cam took shape.


----------



## Swifty

Great going Gus, once you understand what Malcolm is describing, it's easy.

Paul.


----------



## Brian Rupnow

Good stuff, Gus. I was hoping you could get through it okay.---Brian


----------



## gus

Got one good cam with second attempt. Will proceed to cut the steel cams.
The "Bush" aka ''Kampong" DRO just upgraded with "Auto Returm Tension".Will use same for the lathe cross slide for diameter reduction.
The S$3.60 Protractor worked well with the cheapy pointer and white sticker reflector to make easy reading.
Protractor is best versus the Rotary Table degree graduation. Reverse reading is fool proof.


----------



## Swifty

I like the auto return tensioner. 

Paul.


----------



## gus

Swifty said:


> I like the auto return tensioner.
> 
> Paul.



Hi Paul,


I am flattered. 
Since the dial gage did not work,I was so desperate.A DRO from UK would take a week or two come in and fitting it on another problem.The mini mill is too small for "bells & Whistles".
 Am glad the Digital Vernier Caliper worked but I was using my hand to as tensioner and thats dangerous. Did cut one side of the first cam. 
Was surprised that the humble rubber band worked.
With the cheap/nasty tensioner,I could move quill by the .01mm easiliy.

Will cut the steel cams out of 15 mm SAE Grade 5 Galvanised Bolt.
It it a must to harden cam??  
Hopefully by this Friday, I could get a lot more work done.
Weekend fishing coming!!! Fresh fish and chemical free.


----------



## Brian Rupnow

Gus-I have built 6 i.c. engines before I built the Jaguar, and had never hardened a cam until I built the Jaguar. However, on all my previous cams, the tappet has a roller on it that contacted the cam. the Jaguar and the Lynx have a sliding surface tappet, so yes, both the cam and the tappet should be hardened. It's not difficult. Buy some "01" oil hardening steel, machine it the same as any other steel, (it cuts about the same), and then sand any imperfections out of it. Heat it to cherry red and then dump it into a tin can full of old motor oil. That's all you have to do.  This is not a case hardening process, it is a "through hardening process" but hard is hard!!! In fact, it will be so hard that you won't be able to machine it after it is hardened.


----------



## Swifty

You will be putting a lot of work into the cam Gus, so it's probably best to use silver steel and harden it. Brian uses O1, oil hardening, but I prefer to have all my silver steel W1, water hardening. That way there is no mixing up of different types. It's my belief that the W1 is a bit more forgiving if you don't reach the correct temperature, it will always harden a bit. You just have to be a bit careful with sharp internal corners with the W1, the shock of the water quench may cause cracks. I only have a Mapp torch, but this is fine for small components, a small hint to know when you have reached the correct temperature is when you see small bright flakes appear on the red hot surface, this is the structure of the steel changing and it's time to quench.

It may pay to do a small test with your high tensile bolt, just turn up a small part and see if there is enough carbon in it to harden by heating it up red hot and quenching it.

Paul.


----------



## gus

Swifty said:


> You will be putting a lot of work into the cam Gus, so it's probably best to use silver steel and harden it. Brian uses O1, oil hardening, but I prefer to have all my silver steel W1, water hardening. That way there is no mixing up of different types. It's my belief that the W1 is a bit more forgiving if you don't reach the correct temperature, it will always harden a bit. You just have to be a bit careful with sharp internal corners with the W1, the shock of the water quench may cause cracks. I only have a Mapp torch, but this is fine for small components, a small hint to know when you have reached the correct temperature is when you see small bright flakes appear on the red hot surface, this is the structure of the steel changing and it's time to quench.
> 
> It may pay to do a small test with your high tensile bolt, just turn up a small part and see if there is enough carbon in it to harden by heating it up red hot and quenching it.
> 
> Paul.




OK .Guru. I forgot i bought 1/2'' Silver Steel while shopping in HongKong.
Just recalled. Used same for the tail stock centre.The machineability was good. Filing down and sanding gave good finish. However will practice cam cutting with the grade 5 bolt and try hardening. 
Thanks for the prompt reply.


----------



## gus

Hi Paul and Brian,

Thanks for the good advice.  
Up to 2001, I was using electric heat treating furnace and slow/medium/fast quenching oils to heat treat forming rolls,punch and cutters. With all these gone,I am back to very basic heat treatment which I did not pick up. Seen my ''uncles'' heat treating and tempering carbon steel chisels by eye ball and their chisels were the best I ever had.
Will be fun. Will report success and disaster this evening.


----------



## gus

Gus been lying low for 2 weeks ,not doing nothing but trying hard to unravel the black magic art of Cam Cutting on the mill. 
After umptheen bad cams,at last today at 12:30 pm the first good cam rolled out.
The brass cams were easily cut at my first attempt though some improvement required.This made me over-confident.
The second/third/fourth were anything but cams.
Was about to throw in the towel and beg Paul Swifty to sent me some of his good cams.
Good lesson learnt. The quill must be sufficiently tightened to prevent
shift up/down and yet permit down feed. Cam cutting on a small mill is tough.


----------



## Swifty

That's great Gus, but if all else failed, I would have sent you the cams milled on the one piece as mine are.

Paul.


----------



## gus

Swifty said:


> That's great Gus, but if all else failed, I would have sent you the cams milled on the one piece as mine are.
> 
> Paul.



Hi Paul.

Much appreciated. Am glad I traced it to the loose quill and others. And also the the very small increments are not to messed with.
The cheapy M.I.C. HSS endmill also help to add on my woes.:hDe: Now using a M.I.C. Tungsten Carbide Endmill and so far so good. Just bought a quality Indianequivalent and not cheap.  S$48. To standby. The brand is 'Totem''.
Have you come across same. The last Indian 12mm end mill is still sharp after going thru so many mild steel jobs.

Cam blank done. Will finish this last cam piece.


OK .Vertex Accessories are available. This will make retiree Gus poorer.
No sweat. Just made a bundle. So tool shopping no problem.Heading to Fukuoka,Japan with darling boss for our 43 Anniversary. TokyuHands is a big
spread here and 100 yards from Hotel. Will have to lock up my Visa Cards.


----------



## Swifty

Hi Gus, the name Totem sounds familiar, I must have come across that brand in the past. Have a great time at TokyuHands, it may be best to send your wife elsewhere when you go shopping.

Paul.


----------



## gus

Swifty said:


> Hi Gus, the name Totem sounds familiar, I must have come across that brand in the past. Have a great time at TokyuHands, it may be best to send your wife elsewhere when you go shopping.
> 
> Paul.



Fortunately,TokyuHands has got women's department and in the same complex there are many other chain stores. Its each on his own shopping and we meet at 12 noon for lunch and she is always 1/2 hour late and with ample excuses like   ''Gus . I bought this item for you.'''  And of course ,she bought her own other items.;D

Hopefully the last cam gets done today.


----------



## Swifty

Gus, all women seem to be the same when it comes to shopping, "look, I bought you some socks", that's to cover up all the things that they have bought themselves. 

Paul.


----------



## gus

Swifty said:


> Gus, all women seem to be the same when it comes to shopping, "look, I bought you some socks", that's to cover up all the things that they have bought themselves.
> 
> Paul.



Gus married Nellie 43 years ago and 43 years later,have yet to understand her.;D

OK . Second and last cam done rather fast since having picked up the black magic art of ''cam cutting''. Now reading up to tune and fit tappet valves to cam. How much clearance should I go for w/o getting the valves hammering away just like our old Ford cars?
With the Nemett-Lynx Engine we picked up the skill to DIY piston rings and cam cutting. It is true you can't teach ''old dogs'' new tricks.


----------



## Swifty

Gus, I have 0.10mm clearance between the tappet and the cam when it's not working.

Paul.


----------



## gus

Cam rod installed and valves tuned up. Will heat treat and oil quench cam lobes shortly. 

Flywheel will done tomorrow. C.I. flywheel machined on lathe is very messy.


----------



## gus

Heat treatment of cam lobes done. Simple folksy equipement. Buying a whole can of SAE 20 Engine Oil would be very expensive. The 2T oil for now obsolete 2 stroke engines works fine.
Silver Steel is not difficult to heat treat and oil quench. Heat up to bright red and hold for 2 minutes  and by the time cam moved to the oil,the chilly red ccloour came on. Did file test to confirm hardness done.

After clean up , did angular alignment of cam lobes as per Malcom's imperial edict. The DIY RT
with the cheapy protractor performed well.


----------



## gus

Cast Iron is not my preferred material. C.I. is preferred over the expensive brass/bronze. When a job gets to be too big,there is the hazard of sharp chips all over and eventually some may end up on my hands and fingers or foot. 
For cast iron I get dressed up to keep away the C.I. dust on my body which is hard to dust off and the bath room gets rust stained and the boss gets mad.

For some unknown reasons,the Warner Boring Bar gave me bell mouth taper bore at the small end. The Eclipse
HSS Boring Bar saved the day. With the flywheel mounted on,job can proceed into next phase.


----------



## Swifty

Getting close now Gus, I don't know if the boss will be happy with that dirty on one side shirt. It may have been accidental, but in your last picture, you have the belt tensioner on the inside, it should be on the outside.

Paul.


----------



## Brian Rupnow

Looking very good Gus. I am still watching and crossing my fingers for your first successfull run.---Brian


----------



## gus

Swifty said:


> Getting close now Gus, I don't know if the boss will be happy with that dirty on one side shirt. It may have been accidental, but in your last picture, you have the belt tensioner on the inside, it should be on the outside.
> 
> Paul.



My ''BOSS'' did casually asked about the very dirty shirt. My reply was -----"Its
not washable,the cast dust would ''rust'' all other clothings in the washing machine.
Its ''use and throwaway''.

There is an unending stream of mini tasks to finish up before I even dare to think of Spinning the Engine.:rant:


----------



## gus

Brian Rupnow said:


> Looking very good Gus. I am still watching and crossing my fingers for your first successfull run.---Brian



 Hi Brian,

For same reason,I am taking a short holiday in South Thailand to relax before going back to finish up and spin. Promised-------'''Gus will be very patient.''

Now enjoying tackling the mini tasks. Two subassembly to make .

The Carb and Ignition Box and the base and the gas tank. 
The Carb sents shiver to my spine.All my DIY carbs went to scrap bin.:rant:


----------



## gus

Swifty said:


> Getting close now Gus, I don't know if the boss will be happy with that dirty on one side shirt. It may have been accidental, but in your last picture, you have the belt tensioner on the inside, it should be on the outside.
> 
> Paul.




I am confused. Please enlighten Gus.

Please advise Engine direction facing the flywheel.


----------



## Swifty

Gus, you have the belt tensioner running on the toothed part of the belt, pushing it towards the outside. It should be on the smooth side of the belt, pushing it in. The engine runs anticlockwise when looking at the flywheel.

Paul.


----------



## werowance

looking good Gus,  getting anxious to see / hear it run.

question on the cam,  do you polish or anything to remove the "scale" or oxidization caused by the red hot heat?  or does that simply wear / flake off?


----------



## doubletop

gus said:


> ------------------The Carb sents shiver to my spine.All my DIY carbs went to scrap bin.



Cheat?

http://www.hobbyking.com/hobbyking/store/__20455__RCG_15cc_Gas_Engine_Carburetor.htm







That's what I used






Pete


----------



## gus

werowance said:


> looking good Gus,  getting anxious to see / hear it run.
> 
> question on the cam,  do you polish or anything to remove the "scale" or oxidization caused by the red hot heat?  or does that simply wear / flake off?




No .I kind of forgot to remove the scale.:hDe:


----------



## gus

Hi Pete,

I like you engine supports. Looking for ideas. May end up copying Paul Swifty's but its a lot of work.
After a weeks break in South Thailand will have batteries fully charged. I like your carby .Did you DIY it??


----------



## gus

Swifty said:


> Gus, you have the belt tensioner running on the toothed part of the belt, pushing it towards the outside. It should be on the smooth side of the belt, pushing it in. The engine runs anticlockwise when looking at the flywheel.
> 
> Paul.




Lost a Conger Eel. A mate wants to eat it but the guy doing netting bungled and lost it. It was a very beautiful/colourfull eel with very ugly teeth.Back in mind,I rather let it go. Gave me a very good fight 50 feet from sea bottom.
This weekend fishing been very good. 8 pcs on Saturday and 9 today.All Snappers and Javekins. Good eating size to feed 3---4 pax.
Went to a very old spot that we have yet to find out the feed time. Its 1 hour before high tide!!!!. My FADs(DIY artificial reefs) now productive and kept location secret. Will be back from South Thailand next Friday and back to so many things to do!!!. Take care.


----------



## Brian Rupnow

Gus--According to Malcolm Stride, you are supposed to carefully "dress" the machined surfaces of the cam with a fine diamond file before heat treating to remove all of the micro-ridges left by the cam machining process. Then after hardening, you can clean the scale off the faces by rubbing on a fine sheet of carborundum paper. When I made my cams, I got so excited at my success that I immediately hardened them without using a diamond file on them (I forgot that step!!). I did give them a slight wipe on some fine carborundum paper after heat treating. The fact that I missed the "diamond file the micro-ridges before hardening" doesn't really seem to have made any difference to how the cams function.---Brian


----------



## doubletop

gus said:


> Hi Pete,
> .................. I like your carby .Did you DIY it??



Click the link, US$17

http://www.hobbyking.com/hobbyking/store/__20455__RCG_15cc_Gas_Engine_Carburetor.htm

Of course the cam finish needed to be good before you hardened them. Too late afterwards. 

To clean the scale off them just drop them into some clean citric acid mixed in hot water. The cams will them come out a light grey colour which can then be polished with some 600grit emery paper

Get the citric acid crystals from the baking section from you local store. Its what is used by the boiler makers but works on steel. Don't use a mix that copper has been in as it will eat the steel.

Pete


----------



## Brian Rupnow

Gus---Funny story for you (fishing). I have never been much of a fisherman myself, but my father loved to fish lake trout. when I was a kid back in the 1950's my father had a 3 HP Evinrude outboard, a 14 foot wooden boat that he built himself, and he would troll with steel line for lake trout in the big lake I grew up on. He had a big aluminum handled net that he used to scoop the fish up out of the water once he had reeled in his steel line and got the fish up to the boat.  I was at home alone for some reason, and a big bat got into the house. I was terrified of bats (watched too many old Vampire movies at the theater in town.) I ran to my dad's closet and grabbed his big old fish net, and used it to catch the bat out of the air. The bat immediately thrashed about and got all tangled up in the net. I carried it outside, but was afraid to try and get the bat out of the net in case it bit me. (we had all been warned as children that bats carry rabies, and not to get bitten.) I ran into the house and got my mothers big scissors from her sewing basket, and cut the end out of the net, with the bat still tangled in it. I stomped the bat to death, and then seeing what I had done to my fathers fish net, I buried the bat and put my dad's fish net back into the closet. I never told a soul about it. The next time he went fishing, he caught a big lake trout, reeled it in, and dipped it out of the water with the net. Of course, the fish went right through the bottom of the net and gave a big flop and got away. My father come home and said to my mother "I must have put the net away wet and it rotted the bottom right out of it. I caught a big fish and it went right through the net." ---I never breathed a word to my father about what I had done, and the dear man has been in his grave for twenty years now.---Brian


----------



## gus

Brian Rupnow said:


> Gus--According to Malcolm Stride, you are supposed to carefully "dress" the machined surfaces of the cam with a fine diamond file before heat treating to remove all of the micro-ridges left by the cam machining process. Then after hardening, you can clean the scale off the faces by rubbing on a fine sheet of carborundum paper. When I made my cams, I got so excited at my success that I immediately hardened them without using a diamond file on them (I forgot that step!!). I did give them a slight wipe on some fine carborundum paper after heat treating. The fact that I missed the "diamond file the micro-ridges before hardening" doesn't really seem to have made any difference to how the cams function.---Brian



Hi Brian,
After the milling, I went over with hand smooth file,very fine diamond file and fine emery paper. But missed out the scales after heat treatment.:hDe:

No sweat. Cam shaft easily removed to remove scale. This will be done next week after the South Thailand trip. Did not realise 0.01 0r 0.02 is very minute . Gus was heavy handed. Plus the quill was not sufficiently tightened up and this gave me the heartaches and so many ruined cam blanks.:wall:Just another learning curve for Gus.;D


----------



## gus

Hi Brian,

Here's one story,
1. Friend of mine hooked up a 10' Shark Whale and lost it because of a bad net,the handle broke. There goes his fresh sharks fin.:wall:

2. Gus loss a 5' Cobia. The Gaff was to dull to hook up .:rant:

But your incident was very entertaining. Dad would have been mad,if he found out the bat and the truth.

Here is one last one.

Facebook friend in Thailand commented I have yet to give one of my many fish. Just imagine his reaction when
I handed him a 5 pounder frozen Snapper!!!

Had a good Thailand dinner.


----------



## gus

Hard to believe ''Sizzler'' is here in South Thailand. The Steak is up to my taste though ''Medium'' was nearer to ''well done.'' Salad Bar was good. Had to skip dessert as the '' Mousse'' looks very tempting good.
Problem is if I unwind too much,getting to speed to complete and run Nemett-Lynx will be tough.


----------



## gus

Holiday trip over and now back on the saddle. The Nemett-Lynx Engine deserve a good looking exhaust pipe. Hopefully this DIY exhaust silencer will cut down the engine exhaust noise because I plan to vroom vroom it. It took 3/4 day to do plus the silver brazing.
Next on the list would be the Carb.Will take my sweet time to make it and also make it work as it should with Paul Swifty's engine.


----------



## Cogsy

Looking good Gus, can't wait to hear it run.


----------



## werowance

did you use packing (like steel wool or something) in the exhaust or more of a pipe within a pipe with holes in it?  its looking great!


----------



## gus

werowance said:


> did you use packing (like steel wool or something) in the exhaust or more of a pipe within a pipe with holes in it?  its looking great!



Basis not to noisy. If so then mesh pad or heavy steel wool will be used as silencing medium. Thanks for reminding Gus.


----------



## gus

Started work on the carby but while milling the blank to size,the mini mill packed shop on me at 8:30am. With time to kill,I might as well trim blank to size on the mini lathe. Its true skimming on the lathe is faster than milling. 
By 4:30 pm mill both top and bottom end bearings replaced. It was the last two piece the bearing stockist has. With blank marked out. Work carby tomorrow.


----------



## gus

Was making good progress tapping the 8 nos. 2mm holes for the carby flange. Tap broke when I came to the 4th hole.Luckily it did not break inside so no new carb body rework. Worked stopped as that was my one and only Japanese M2 Tap.  Will work on the barrel and others tomorrow.
The ''Bush'' DRO was dismantled but put back in place to mill carb blank to required thickness. Same DRO will be left mounted on mill. Later in the future will improve overall appearance of Bush DRO to render it not so Bushy.


----------



## Brian Rupnow

Hi Gus---For some reason I am not being notified when you post. I like to keep track of your progress, so will post something here again and hope that will fix things.---Brian


----------



## gus

Brian Rupnow said:


> Hi Gus---For some reason I am not being notified when you post. I like to keep track of your progress, so will post something here again and hope that will fix things.---Brian



Hi Brian,

This week should see the Nemett-Lynx very near to completion except the start&run. Carb done.


----------



## gus

After so many years of hit and miss silver brazing, I succeeded brazing brass to brass.
Tried placing job on a piece of plaster of paris brick left over from casting lead sinkers. Was surprised the Camping Gas Torch was enough to bring it up to brazing temperature and the tiny bit of 40% silver rod melted and sink into the joint . For insurance I added on a glob more. Previous brazing jobs were place on vise and took long time to reach brazing temperature with Brazing Gas--- Mapp Gas. 
Will make a ''Bush" brazing hearth for future brazing jobs.
Carby incline mounted on engine less spray bar. Spray Bar will be another challenge as I have never attempted such a extended deep 0.8 mm hole. Will give three attempts. Failure of which will beg/borrow/steal/buy/exchange one complete set from my good friend Paul Swifty.


----------



## Swifty

Hi Gus, just take it easy when drilling the 0.8mm hole in the spray bar, peck at it and clear the chips often. Use your highest speed as well and you should be ok. Otherwise just let me know and I will send you one. On a 14x39 lathe, it was a real challenge for me as well.

Paul.


----------



## gus

Swifty said:


> Hi Gus, just take it easy when drilling the 0.8mm hole in the spray bar, peck at it and clear the chips often. Use your highest speed as well and you should be ok. Otherwise just let me know and I will send you one. On a 14x39 lathe, it was a real challenge for me as well.
> 
> Paul.



Hi Paul,
Thanks for standing by Gus.

Spray Bar done. Was nail biting drilling the 0.8 mm hole. Did the pecking and withdrawal as per your expert advice.
Bought some micro drills from TokyuHands long time ago and these drills performed well. Will do the Fuel Needle in the afternoon. Same looks not too
scary.


----------



## Swifty

I raided the wife's sewing box for a suitable darning needle, worked really well. 

Paul


----------



## gus

Swifty said:


> I raided the wife's sewing box for a suitable darning needle, worked really well.
> 
> Paul




Hi Paul, 
Good Day. Soon after reading your post I did same and found a 1.4mm needle which fit in.
The one and only I had was a dud with sharp point missing.


----------



## gus

OK .Carby assembled,adjusted and done.  The throttle lever is a ''temp'' and very Bushy Job. Will figure out a good looking one.
Will go on to finish up the Ignition Assembly. Start up by end next week looks possible but I am not gunning for it. Still have to figure out the Electronic Ignition.


----------



## Brian Rupnow

Gus---That's a great looking carburetor!!!---Brian


----------



## gus

Now figuring out the layout that is engine,fuel tank and Ignition System. Will take a week or so and no hurry.
Now taking my sweet time to admire my 5 months' labour. The engine support will be '' Simple Simon'' as my mini mill will be overstretched to cut fancy profile.The fuel tank will be a surprise.


----------



## Swifty

Not far away now Gus, I'm as keen as you are to see it going.

Paul.


----------



## gus

Swifty said:


> Not far away now Gus, I'm as keen as you are to see it going.
> 
> Paul.



Hi Paul,

Now that I am so near the finishing(line),I am so relaxed(lazy too) and walking slowly to completion. Now raining heavily with a wee bitty teeny droplets into the 3 open sided machineshop, I have good excuse not working. Will enhance the throttle lever.

Now figuring out how to house the ''Electronic Ignition Kit..

I have "Pet Engine'' sitting next to my Apple N/book.

Two magnets in Timing Disc. Is this a must??


----------



## doubletop

gus said:


> Hi Paul,
> 
> .
> 
> Two magnets in Timing Disc. Is this a must??



Yes two magnets; as you are using a CDI the timing delay will be wrong as it will think you are going half speed. CDI's have no concept of revs. They only know about time intervals and need to know how long it is going to take for the *crank* to move from the trigger point to the TDC. With the camshaft going at half speed it takes twice as long and the firing point is then late.

Pete


----------



## Jasonb

doubletop said:


> Yes two magnets; as you are using a CDI the timing delay will be wrong as it will think you are going half speed. CDI's have no concept of revs. They only know about time intervals and need to know how long it is going to take for the *crank* to move from the trigger point to the TDC. With the camshaft going at half speed it takes twice as long and the firing point is then late.
> 
> Pete


 
Not quite true for all CDIs, only applies to ones with auto timing, if you use one from the likes of S/S it will only need a single magnet on the cam as it does not need to know how fast the engine is running and saves wasting a spark.

J


----------



## doubletop

Jasonb said:


> Not quite true for all CDIs, only applies to ones with auto timing, if you use one from the likes of S/S it will only need a single magnet on the cam as it does not need to know how fast the engine is running and saves wasting a spark.
> 
> J



Jason  

Thanks for helping to avoid confusion but Gus was asking about using an Rcxel ignition which does do auto timing 

Pete


----------



## Swifty

Gus, I know that you have been having a bit of a break, but any longer and you will forget where you got to. I'm keen to see your engine running, as I'm sure others are. 

I've been having a rest myself after finishing my Lynx, haven't started any other projects yet, but it's still amazing that I manage to fill the days in.

Paul.


----------



## fishy-steve

I'm with you Paul.
Pull your finger out Gus!!! 
We need to see this engine running.

Steve.


----------



## Brian Rupnow

Gus--I have the feeling that something has gone wrong over there. I hope your health is good, and I hope that if you are suffering from "Machinist burn-out" that some time away from model engineering will fix that. Please let us know what is happening. --We worry about you when we don't hear from you.---Brian


----------



## Swifty

I think that Gus is away fishing for a while.

Paul.


----------



## fishy-steve

If that's the case then Gus really sounds like my type of guy!


----------



## gus

Brian Rupnow said:


> Gus--I have the feeling that something has gone wrong over there. I hope your health is good, and I hope that if you are suffering from "Machinist burn-out" that some time away from model engineering will fix that. Please let us know what is happening. --We worry about you when we don't hear from you.---Brian



Hi Brian and Paul

No worry. Gus just got back after a week of great fishing in Kuching,Sarawak---land of head hunters hundreds of years ago. The '' 
Native Dyak'' head hunters missed Gus and so my head is still intact. Three days fishing. First day was bad. Second was  also (bad) with non-stop fishing. Six big fish out of ten drops. Third day gave up my spot to the trip leader.See foto. My darling wife is so happy with the Red Snappers and we will have quite a few rounds of Curry Fish Heads for dinners.
Now busy extracting the lazy bones. Nemett-Lynx engine should be up and running this week.


----------



## gus

Alrighty. Gus on the saddle now with lazy bones totally removed.
Here's my Hit List.
1. Make base c/w Formica.(Done 11 am 20th Oct ,see foto)
    (Exotic hardwood very expensive here. Use surplus Marine Plywood)

2. Fuel tank.( Blank Fuel Tank done/capped both ends today at  5pm 20th Oct.)  ( Gas tank mounted on. Work on schedule as promised. 21st Oct 4:30pm)

3. Cranking device as per Paul's

4. Hall Effect Adapter

5. Tune up all timing, cams , valves and igniting.

6, Run.

Will report progress.  However Gus has to have his right eye checked today to confirm cataract ripe for operation next month. So best to get engine spinning.


----------



## gus

fishy-steve said:


> If that's the case then Gus really sounds like my type of guy!



Hi FishySteve,

Are you an angler too??  
You are welcomed on to my boat,if you visit Singapore. Gus has too many hobbies and so little time. It is true when engines get too tough to make,I do get burnt out and hence need to rest/switch my brains to do something else but engines. Carpentry and fishing are good escape venues. 

Take care.


----------



## fishy-steve

gus said:


> Hi FishySteve,
> 
> Are you an angler too??
> You are welcomed on to my boat,if you visit Singapore. Gus has too many hobbies and so little time. It is true when engines get too tough to make,I do get burnt out and hence need to rest/switch my brains to do something else but engines. Carpentry and fishing are good escape venues.
> 
> Take care.


 
Hi Gus.
I do indeed fish. Mostly flyfishing for trout on inland  lakes and rivers.
On my list of things to do is a visit to Singapore for the Grand Prix.
 Steve.


----------



## gus

Gus been doing carpentry for too long. Tried a mixed of carpentry and metal bashing and came up with a clip bending jig in 5 mins. Its a must to anneal brass strip for easy hand bending.
The last all metal bender gone with the wind.


----------



## gus

At last my engine is all prepped to run early next week. The Hall Effect Sensor probe not done yet.
Timing all done .Compression good but whether its good enough to ignite and run.


Fuel Tank and mounting clips are very much a borrowed invention from Paul.
Thanks .Paul. IOU beers.


----------



## Swifty

Gus, I did mention in another topic where you had posted a picture of the fuel tank, be careful, it may be a bit low. The fuel has to be sucked up a fair way, if it can suck up this far, you may need a non return valve. Just my first thoughts.

I'm getting excited to see it running, it looks as though it ready, don't tell us that you are going fishing again this weekend 

Paul.


----------



## Swifty

Gus, you asked about the prop on another topic, I decided that I would reply here to keep it all neat. The prop I have is 15" dia x 5" pitch. The pitch is not important as it is only for display, I found that the prop is too light to keep the engine running, perhaps with a bit of loosening up it may be ok, or maybe I can make a heavier prop drive to give it some weight. I searched all over ebay for a prop, but finally found a suitable one at a hobby shop nearby for A$20.

Paul.


----------



## gus

Swifty said:


> Gus, you asked about the prop on another topic, I decided that I would reply here to keep it all neat. The prop I have is 15" dia x 5" pitch. The pitch is not important as it is only for display, I found that the prop is too light to keep the engine running, perhaps with a bit of loosening up it may be ok, or maybe I can make a heavier prop drive to give it some weight. I searched all over ebay for a prop, but finally found a suitable one at a hobby shop nearby for A$20.
> 
> Paul.




Thanks for the info.Will shop for a 15'' prop.

Or I might make a stubby prop out of pinewood just for fun. Will be very relaxing DIY prop. My spokeshaving skill is junk. Will take this opportunity to practice and improve this skill. 

OK .Told my fishy mate,too tired to fish tomorrow. Will try spinning engine tomorrow.


----------



## doubletop

I'm using a 16"x6" from HobbyKing.

http://www.hobbyking.com/hobbyking/store/index.asp

 I was interested to hear of Swifty's experiences with a prop and a flywheel which makes me think of trying a flywheel at some time.

Pete


----------



## gus

Paul gave me good advice. The fuel tank is a wee bitty low and best to put in a check valve to prevent gas flowing back to tank.
OK .Done . Recycled check valve from H&M Engine. No fishing today. Coming to the very last item. Adapter for the Hall Effect Sensor. Will be done by 5pm today.
No fishing today. Spent the morning mopping up and recuperating from the after effects of SeaSick Pills.Must have been a new brand not good for Gus.


----------



## gus

Went shopping for 14'' prop. Cost me S$10. or A$8.00.''Scimitar Profile Master Airscrew.''
Cutting my DIY prop will be too labour intensive/time consuming.


----------



## gus

Day One.
All rigged up. Getting very good compression but CDL not firing. Spark Plug have not sparks. 

SOS. Is magnet strength and polarity of magnet important?? Distance gap between magnet and Hall Sensor important?


----------



## Jasonb

Yes magnet has to face the right way round, about 1/32" gap


----------



## Cogsy

On my Chinese copy, the magnet definitely has to face the right way, but the gap can be anywhere from almost touching to 4-5mm away and it will still spark.


----------



## Swifty

As the others have said, the magnet has to have the correct pole facing towards the sensor. If you check my Lynx build, I did mention a method of finding out which is the North or South pole of the magnet. I'm not at home at the moment, so have limited internet access, otherwise I would look it up for you.

Paul.


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## Cogsy

The easiest way I know of to determine the correct poles of a magnet is to use a compass. Hold the magnet near it and see which end the North pointer points at. That should be North pole of the magnet if I remember correctly.

All I do for hall sensors is randomly choose a pole of the magnet and wave it over the sensor. If it doesn't spark I reverse it.


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## gus

Ok. Got it.  Will get Sparks going. The CDL is new trick for ''old dog'' used to Contact points and HT Coil..

I have another backup set bought for the Webster and Rupnow H&M for 10mm plug. 

Will go all out today. Compression was very good. Very hopeful will make a few pops today.


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## gus

OK . Got the sparks but Timing Disc and housing not suitable. Will cut and clone Paul's .

Meanwhile will  hunt for suitable magnets.


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## gus

Cannibalised 4mm magnet from Magnetic Pickup Socket Spanner.  Getting  very good sparks.

Fuel delivery from not ideal low level fuel tank stabilised with check valve.

Engine just won't start. Not even popping. :wall:


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## Cogsy

Hmmm, if you have good spark, good (enough) compression and fuel then it 'should' fire. If you've fiddled with the carb needle enough and it still won't do anything then I'd try the ignition timing. I'd try altering it in one direction and keep altering it until it either begins to fire or you've changed it so much you can rule it out as the cause.

I'm sure you'll get it Gus. If it was easy it wouldn't be fun!


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## gus

Cogsy said:


> Hmmm, if you have good spark, good (enough) compression and fuel then it 'should' fire. If you've fiddled with the carb needle enough and it still won't do anything then I'd try the ignition timing. I'd try altering it in one direction and keep altering it until it either begins to fire or you've changed it so much you can rule it out as the cause.
> 
> I'm sure you'll get it Gus. If it was easy it wouldn't be fun!




Thanks. Cogsy. 

I thought the Rupnow H&M Engine was tough.Took quite a long while getting the Hitting and Missing to happen. Almost gave up. 
Will be fun and surprising when I get to the cause.  Taking a break now.


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## Nicolas

Hello Gus,

I just had a look through your build so far.

Great work so far, keep it up


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## gus

Nicolas said:


> Hello Gus,
> 
> I just had a look through your build so far.
> 
> Great work so far, keep it up



Hi Nicolas,

DIY I.C. Engines has a very bad habit of not starting at the very first few sessions. Hopefully it will pop a few times and from there run a few seconds.
Getting the valve timing right and ignition timing is first step. Tuning the fuel jet quite tricky.I am jinxed, all my three engines happened this way.:wall:

Part of learning curve. Having fun just trying to get engine started and running and vroom vrooooommmm.


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## gus

OK. Done all trouble shooting. Valve timing not correct.  At the crack of dawn will run engine.


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## gus

Good News,

I got a few pops and ran for 5 secs. Means I am getting near. Battery about flat.Now recharging and let starter cooled down a wee bit. I did burnt a starter with the GrassHopper Engine last year.


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## Cogsy

Good to hear Gus. It won't be long now. Remember to do a video once you get it going.


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## gus

At long last after the few pops,and some fine tuning advancing/retarding ignition ,got her running non-stop till shutdown after 22 secs.The pops did cheer me up. Please visit my FaceBook Post under Augustine Teng.
There are two videos,the first w/o silencer and the second with.
I need help to post a good video on YouTube and then to this forum when engine is tidied up.
Will spent the next two months running this engine before heading for other projects.
HMEM Folks. Thank you much for giving Gus your timely expert advice,support and encouragement to finish up and run this wonderful unforgiving engine. I did get sleepness nights and near burnt-outs.


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## Brian40

Well done gus another remarkable achievement.

 Brian.


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## gunna

Congratulations, Gus. A great looking engine.

Ian.


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## Jasonb

Weld done Gus, good to know its a runner


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## Cogsy

Congrats Gus. It runs really nicely and responds well to the throttle already. Nice work!


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## Brian Rupnow

I knew you would get there Gus.--Congratulations.---Brian


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## ShopShoe

Congratulations Gus. I always look for your latest adventure postings from your balcony (and your boat) when I log in. I did not have any doubt you'd get it running.

--ShopShoe


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## werowance

great job Gus,  congratulations!


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## doubletop

Great new Gus - lets see the video as soon as you can please

Pete


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## Swifty

Well done Gus, I've had limited internet access the last week, as I've been away from home. It's great to log on and find that you have a runner. I will go and check out the video on facebook right away. What shall we make next?

Paul.


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## Swifty

Gus, facebook won't let me into your 2014 postings, so I have sent a friend request.

Paul.


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## fishy-steve

I can't see your video either Gus. I've also sent a friend request. 
Looking forward to seeing the vid!
Steve.


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## Brian Rupnow

Gus--There are many of us who do not subscribe to Facebook. Please post your video on Youtube and post the link here so we all can see.---Brian


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## fishy-steve

Hi Brian.

Try here.

IMG 2038: http://youtu.be/wo1YWfNiDGQ

Great to see it running! 

Steve.


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## canadianhorsepower

what is the bore and stroke of this Lynx
 congrat GusThm:Thm:


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## Brian Rupnow

Very Nice Gus.--Congratulations!!---Brian


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## Swifty

canadianhorsepower said:


> what is the bore and stroke of this Lynx
> congrat GusThm:Thm:



It's a 25mm bore with a 30mm stroke.

Paul.


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## bmac2

Gus. Congratulations on yet another runner. I knew you had it in you. Thm:
I personally think you are truly inspirational for anyone with limited space and equipment. With each new build you prove time and again that you dont need CNC, a Bridgeport mill or a lathe with a 10 swing to get into this hobby. Patients and ingenuity will get you there every time :bow:


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## Niels Abildgaard

Hello Gus

Nice engine and state of art valves and overhead camshaft.
Sometime ago a gentleman wanted some IC advice

http://www.homemodelenginemachinist.com/showthread.php?t=21515

for a honorable job.
An engine like Yours is not a mile of for making 100 200 Watt.
Do You know if anybody has measured fuel efficiency on a Lynx?


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## gus

fishy-steve said:


> Hi Brian.
> 
> Try here.
> 
> IMG 2038: http://youtu.be/wo1YWfNiDGQ
> 
> Great to see it running!
> 
> Steve.




Hi Steve,
I did succeed putting it on YouTube but could not get it into HMEM Forum.But somehow from YouTube,it went to FaceBook.
Thanks for making it viewable on HMEM.Please give your expert advice.

For the whole five months I was too shy to give up.I chewed on an engine that I could not swalloe and digest. All other items were not too difficult but the OuterHead had so many sub-assembilies to make and fit on.All these mini items demanded attention.It was the impatience that nearly ruined this project but sheer stubborness,obstinacy,pride and encouragement from HMEM Folks greatly helped to struggle on to completion and running this very unforgiving engine.The OuterHead was made twice and so was the cam box.

At last I did get to sleep well with a smile on my face. 

Was great to have a wife to share my success. Bought her good lunch.


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## Cogsy

Gus, for any Youtube video just copy and paste the whole Youtube web address (starting with http...) into a normal post on HMEM and the video will display. At the very least it will provide a link to the video.

Congrats again on a great runner. Your success has inspired me and I will be beginning my own challenging build next week.


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## gus

Hi Al.

Thanks for the expert advise on youtube posting.

As for Nemett-Lynx Engine, my problems were  1. Not reading individual plan and dimensions especially the centre distance between holes carefully. 2. Impatience.

*OuterHead*
Same is a major sub-assembly of a number of sub-sub assemblys which I failed to recognise.
Sub-Assemblies:
Cam-box/exhaust pipe/air intake/carb/ camshaft and cams/spark plug hole.
All together I had to make new pieces for O/H,Cam Box. Messed up spark hole and had to labourously re-work. Best to have the 1/4'' spark plug on hand to confirm hole depth so as to have plug end to protrude beyond O/H. 

Next project will be the DIY MiniMagneto to drive the Webster Engine built last year.The kit cost me a bomb. Been reading up on mini magnetos. Plan to build one more if I can find the antique bicycle dynamos. The silicon steel laminations is not a problem as I plan to rob from discarded transformers.


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## Jasonb

Gus, Model Engine Builder magazine had a design for a nice mag that was quite a bit smaller than the Minimag one, think it was called the Vieti-mag.

J


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## doubletop

[ame]http://www.youtube.com/watch?v=wo1YWfNiDGQ[/ame]


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## doubletop

The trick is getting the YouTube link in the correct format. They will give you a link like this

http://youtu.be/wo1YWfNiDGQ

  All you'll get is the URL displayed. Which you can click on and go to YouTube

But if you enter the information in the format



		Code:
	

http://www.youtube.com/watch?v=wo1YWfNiDGQ


directly into the post the HMEM website will interpret it correctly and show the video in your post

Try it

Pete


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## Swifty

Hi Gus, are you using petrol or shellite (coleman fuel) to run the engine.

Paul.


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## gus

Swifty said:


> Hi Gus, are you using petrol or shellite (coleman fuel) to run the engine.
> 
> Paul.



Would like to try Coleman but not available here. Used Shell ''95''. The Jerry Can is about dried up .May go over to ''Shell V Power.'' Will report perforamnce
drop or improvement.
Will be away Nov 6-----10 for the "Floating Lantern" Festival where Single Women launch same and make wish for ideal husband. Taking fotos.
At 71 Gus is too old to qualify. :rant:
Happily married to Nellie for 43 years.
We have same festival and same lighted lanterns in China but not seen it yet.


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## gus

doubletop said:


> http://www.youtube.com/watch?v=wo1YWfNiDGQ




Hi DoubleTop,

Thanks for your kind help.
Now taking a break. Going to Thailand for a short holiday,Nov 6-----10.


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## hblair

I also bought the Model Engineering magazine a few months ago.  I have started the engine.  So far I've built the Cylinder sleeve, the air cooled cylinder and have started the crank case.  My local supplier didn't have 2 1/2" square stock so I bought some 3" square and have whittled it down to size.  I should have the crank case finished this week.
For each piece, I've made my own Autocad drawings, and converted them to imperial measurements.  This gives me a in-depth look at each part before I start cutting metal.


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## canadianhorsepower

hblair said:


> I also bought the Model Engineering magazine a few months ago. I have started the engine. QUOTE]
> 
> Can someone tell me witch book I need for this build I have the book number they mention but the plans are not included:wall:
> 
> 
> thanks for your help


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## Swifty

Luc, if you go back to post #1 in this build, you will see the magazine that had the drawings included. You may be able to buy a reprint, check out there website.

Paul.


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## canadianhorsepower

Swifty said:


> Luc, if you go back to post #1 in this build, you will see the magazine that had the drawings included. You may be able to buy a reprint, check out there website.
> 
> Paul.


 
 Ok thanks Ill have a look


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## Jasonb

Get one while you can

http://www.myhobbystore.co.uk/product/172326/best-of-model-engineer-volume-3


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## canadianhorsepower

Jasonb said:


> Get one while you can
> 
> http://www.myhobbystore.co.uk/product/172326/best-of-model-engineer-volume-3




 Just did thanks

 Luc


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## derek999

Hello guys

Just found and read this post with great interest and a certain awe!

I aspire to build this engine once my workshop is built and operational, next year. Conditions are too cramped and cold until then as winter has arrived.
This post has given me great encouragement and impetus.My materials collection is gradually meeting requirements.

What I have seen though is, I feel, a fitting memorial to the genious we recently lost. He will be very greatly missed.

I wish all a very happy Christmas and a prosperous and healthy new year.

Derek


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## hblair

I've got a good start on the engine.  The front nose is finished, the air cooled cylinder is finished, the cylinder liner is finish.  I made a crankcase, but broke off a tap in one hole and a drill bit in another, and wasn't able to them out easily, so I'm re-making the crank case.   I'm doing autocad drawing of each part as I make it, with inch dimensions, which is a  real pain.  The only probem with metrics is when I work on the lathe, and need to crank in a few thou on the dials.  So far is is fairly easy to build.  Just don't use 6-32 screws unless you have too.


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## Brian Rupnow

hblair--You're crankcase is aluminum, right? haven't you tried the alum dissolved in water trick to chemically dissolve the tap and drill?---Brian


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## doubletop

hblair said:


> I've got a good start on the engine.  The front nose is finished, the air cooled cylinder is finished, the cylinder liner is finish.  I made a crankcase, but broke off a tap in one hole and a drill bit in another, and wasn't able to them out easily, so I'm re-making the crank case.   I'm doing autocad drawing of each part as I make it, with inch dimensions, which is a  real pain.  The only probem with metrics is when I work on the lathe, and need to crank in a few thou on the dials.  So far is is fairly easy to build.  Just don't use 6-32 screws unless you have too.



HB and others

There are a number of us who have done this engine. Start your own thread, give us photos and we'll help you when we can.

Most of all enjoy your journey knowing you have our support

Pete


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## Swifty

To those that may not have seen it, I'm another one that has built this engine, build log here http://www.homemodelenginemachinist.com/showthread.php?t=23065

The avatar on the left is my engine.

Paul.


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## gus

Swifty said:


> To those that may not have seen it, I'm another one that has built this engine, build log here http://www.homemodelenginemachinist.com/showthread.php?t=23065
> 
> The avatar on the left is my engine.
> 
> Paul.




Paul,
Your engine looks good on Avatar. I am still looking for a piece of hard wood to make the base,Lacquer it and put on a prop. Prop now on my PC Desk.
Still messing with the Sander and Power Feed or rather enjoying them like a young kid.


My GrandChildren want battery power pencil sharpener for Christmas. Advised their mum, I will also include lotsa lead pencils too. This is jolly well knowing what we did as young kids with the very first desk mount rotary sharpeners. Lotsa reasons to keep sharpening the pencils too often and too many times.

Take Care when driving. Too many drink/drivers on the road for Christama..:rant:. Was stopped by police while driving on the Great Ocean Road for breath test. Your police was quite nice fellow and remarked I did well on breath test. Gus not a day time beer/wine man.


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## Swifty

Hi Gus, looks like we both have too many things to work on at once, I recently bought a camping trailer, although it was in pretty good condition, I still wanted to paint it a bit as it had a lot of stone chips on the paintwork. It's given me another project to work on, here's a link to the manufactures web site, http://tracktrailer.com.au/tvan/ although ours is a late 2005 model. There are plenty of off road areas that we want to explore still, been around Australia with a very good off-road caravan checking out the outback areas, but that was a few years ago.

Pencils won't last very long with an electric sharpener, I use to have a hand crank one, it's amazing how fast it eats pencils.

Nothing has changed with the random drink driving checks, probably even more this time of the year, and nowadays looking out for drugged drivers as well. I'm like you, don't drink during the day generally, a beer or wine at night is nice, although with me being on dialysis, my fluid intake is serverly restricted. Police here generally are great, maybe I'm a bit biased as I have 2 sons in the police force.

Paul.


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## mrehmus72

Jasonb said:


> Gus, Model Engine Builder magazine had a design for a nice mag that was quite a bit smaller than the Minimag one, think it was called the Vieti-mag.
> 
> J



The John Vietti magneto worked OK but would not start a cold engine. The improved design, by Don Grimm, will. You can find it in Issue # 10 of _Model Engine Builder_ magazine.
Mike Rehmus


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