# ShedBoys' First Engine



## ShedBoy (May 21, 2011)

I was going to build a free piston jet engine as my first but I am Having some issues finding a 125mm round piece of Ali. So I thought I would give a plumbing engine a go. It may not work, If it does it will only be for short runs because heat will be a problem. Worse case I could make a new head and run it on air. Not a great deal off planning just some basic parameters. Started with this part and a ruler to get a bore and stroke and used an engine design spreadsheet I found on the net which seems to put out some good info. This is a learning experience for me so feel free to steer me in the right direction. Sorry about some iffy photos.





The plumbing part found in bunnings 14.6mm bore




Machined down end for a cylinder deck ring, said deck ring and spark plug adapter.




Silver soldering them all together. Still need to pickle it? Can anyone tell me what to pickle it in?




Soldered cylinder. I need to practice soldering


----------



## ShedBoy (May 21, 2011)

Deck squared up and then it was bored. Sparkplug thread was chased after soldering.




Drilling the head bolt holes.




Tapping. Is this an okay practice for tapping, I only use light pressure on the quill?


----------



## ShedBoy (May 21, 2011)

The head was turned from some type of steel which I had in the box. Does not machine to nicely. Simple stepped turning.




I am using sunken cap screw to hold the head on. Here is how I recess them. I need some counterbores one day.




The head fit a good start. Sparkplug and head on to give an idea of layout.


----------



## ShedBoy (May 21, 2011)

Righto the bit I reckon I am going to do more than once. Trying to get the valves in. I am going tp call this an unsquare engine on account of my unsquare looking head bolt. I am definately going to buy a wiggler or maybe a laser edge finder. Oh well back to the action.




Valve holes, drilling to heights, three different size drills in each hole and lots of collet changes.




More unsqareness, hate to ruin a theme. Down the bore which needs honing still.




Drilling the ports and mounting the rocker pivot should be fun. With that thought I went to bed.


----------



## Chitownmachine (May 21, 2011)

Yer tapping method is in my opinion the best way to tap. Drill the hole and tap the hole with the bed in the same position. No alignment issues then, and less broken taps. Looking really sweet!


----------



## maverick (May 21, 2011)

I agree, Drilling and tapping without moving the table is the way to go. More taps have been broken by misalignment or
applying a side load. With this method even 0-80s are no problem. 
Good luck with your build.

Mike


----------



## Steam4ian (May 22, 2011)

G'day Shedboy

Pickle, you will find citric acid works OK.
The advantage is that it doesn't eat your clothes. You can purchase the crystal from home brewing suppliers in 0.5 or 1 kg bags. I just stir it in until no more will dissolve.

Sulphuric acid is now available as drain cleaner if you want to go for something stronger, I think Bunning have that as well in a brown plastic bottle. You need a 10% solution and remember to add acid to the water not the other way around. take the usual safety precaution, like rubber gloves, face shield and plastic apron, make s citric acid seem a doddle.

Keep us posted

Regards
Ian


----------



## ShedBoy (May 22, 2011)

Citric acid sounds too easy, I will go wth that. Got to go to work for another week . Back to the shed next week.


----------



## T70MkIII (May 22, 2011)

ShedBoy  said:
			
		

> I was going to build a free piston jet engine as my first but I am Having some issues finding a 125mm round piece of Ali.


Have you tried Robert Cameron Engineering in Burswood? I don't know if they have 125mm but they are sure to have something around that size or larger, and are very happy to cut off small lengths for hobbyists. I feel guilty every time I go there and ask for less than 0.5m of something, but they are great guys and just charge by dimension. Aaron or CJ in the office, and George in the workshop - great people.


----------



## cfellows (May 22, 2011)

Interesting looking engine you got going there. What's the bore and stroke going to be?

Chuck


----------



## ShedBoy (May 22, 2011)

15mm bore 25mm stroke. I think my valve are a bit close together so I will probably need to make a new head. Will see. Vacuum inlet maybe a governor on the exhaust valve to stop it running (if it does) too quick. I will make some proper plans while I am at work away from the shed.


----------



## ShedBoy (May 23, 2011)

Robert Cameron Engineering sounds good I will give them a go. Thanx T70


----------



## picclock (May 23, 2011)

Hi ShedBoy (great name)

>> engine design spreadsheet 

any chance of a link ?

Looks like an interesting build, especially sealing those tiny valves. Await your next instalment with interest.

Best Regards

picclock

(shed frequenter)


----------



## ShedBoy (May 23, 2011)

picclock  said:
			
		

> Hi ShedBoy (great name)
> 
> >> engine design spreadsheet
> 
> ...



Send me an email and I will forward it on as I can't find the link again but have a copy of it.


----------



## ShedBoy (May 30, 2011)

I am about to fly home YAY! Any idea for valves. Will the steel be okay for seat or should I put in some tiny inserts or cages? They are about 6mm round. Just found some interesting things at work while rummaging in the bin. One is about 1.5kg brass bush, should be good to melt down. Need a furnace I think. Too many thoughts I am going to pop. To the shed boy wonder.


----------



## ShedBoy (Jun 2, 2011)

Back in the shed finally today. First up make the new quick chnge tool post fit. Just needs a trim.




Turn some valve guides from brass. I am going to cut seats in the head, see how it goes.








Two guides done so far so good.




My first attempt at turning a valve. Not a tiny turner yet me still a bit gun ho. Baby steps.
Or is that baby cuts.


----------



## ShedBoy (Jun 2, 2011)

Second go at valves went a bit better, just need to take small cuts to match my small valves.




Don't rush it Brock is my new mantra.




I left some extra on it because I was unsure how I was going to stop the spring coming of. Need some e clips 2mm




Found some tiny E clips and made myself a cutter out of an old hacksaw blade.




Worked better than I thought it would and I was able to use it to part off the valves

Thanks for stoping in
Brock


----------



## ShedBoy (Jun 2, 2011)

Now got two valves and a head with guides  I am shocked I only broke one valve.




Need to make a valve seat cutter tomorrow that is going to be fun. Does anyone know how to identify rill rod by eye?
I have a heap of shafting from a photo copier it looks silver and very uniform size. Oooh while rummaging around in my container of Photcopier stuf I found some interesting stuff.




Ready made main bushes, phosfour (need spell check) bronze and I have the 10mm shaft that come from it.
Crankcase and crank tomorrow.


----------



## ShedBoy (Jun 2, 2011)

Gee my photo taking is hit n miss a bit lie my spelling. I choose to blame the keyboard.
More tomorrow.
Brock


----------



## ShedBoy (Jun 2, 2011)

My crappy scribble plans got in a picture. Please ignore them.
Brock


----------



## picclock (Jun 2, 2011)

Hi Shedboy

Looking very good, be interested to see it running. Re making the valves - If you turn between centres, using a centre in the tailstock leaving the head of the valve unfinished until the final parting off, the work will be much stiffer and easier to machine. If the material is not hardened yet you will likely get a better finish using an HSS tool. After you part off the valve head it can be cleaned up on the grinder if needed.

As a rule of thumb unsupported turning length should be up to 4x the work diameter. This is of course rubbish if you work out that the deflection strength varies with the square of the cross section, but for a rough guide on modeller size stuff its not far out. For very thin stuff it should be less .. .

Many thanks for the informative pictures.

Best Regards

picclock


----------



## ShedBoy (Jun 2, 2011)

Thanx for the advice picclock. The first valve I did turn with a centre in the tail stock and it snapped on a 0.25 pass. I need to make a tiny point for the live centre. The next two were done in a step turning fashion with 0.15 roughing cuts. I just recieved some HSS tools yesterday evening. I have only ever used inserts before and not much fine work like this. This engine is helping with skill building, it is being built to run but it may not.
Tool grinding rest today I think and then a valve seat cutter.
Brock


----------



## picclock (Jun 2, 2011)

Hi Shedboy

What metal are you using for the valves ? to snap with only a 10 thou cut is not good. Is the tailstock properly aligned ?.

HSS will make a huge difference here as the edge is much finer and the pressure on the work is far less, I would estimate a 1/3rd or less. You do need to hone up the edges quite often, but you quickly get to tell when the edge is going by the feel and look of the cut. I use a piece of India stone soaked with oil. 

If you leave the extra at the end of the valve face, about 6mm thick you can just drill it with a normal centre drill - no special parts needed. Part off at the end of machining and throw away the drilled part.

I'm currently moving my lathe into another room (air conditioned 8) ) but am having to make up the work surfaces. Trouble is I hate woodwork and the dust seems to get into your lungs clothing and everything else (and I'm cutting the timber outside ).

Good luck with the engine.

picclock


----------



## ShedBoy (Jun 5, 2011)

I am unsure of the material I used. I do know that it is magnetic, very bright, precision ground shaft. I scrapped a photocopier to get the stepper motors from it and there was alot of these shafts and bushes. 
Any idea what it would be or is there some way I could test it? 
You mention hardening valves is this the same process you use for tooling (harden then temper)? 
Would I be better off making the valves out of stainless steel?

I got some HSS and have made a rest I just need to put a gurd around the wheel and bolt it all down so I can use it. I think I will still use my tipped tools for roughing cuts and then finish with HSS. Any thoughts?


----------



## steamin (Jun 5, 2011)

Hi Shedboy, Looking real good for your first engine. I am guessing you are taking this on by yourself without any mentor around. If so, you are doing a fine job and you have come to the right place to share and get some advice and help. Let me pass a couple of machining tips on to you.
1] Carbide cutting tools require more tool pressure to start and maintain the cut than does high speed steel tool bits. For small delicate items I will always use HSS tool bits with a slight radius on the tip for a smother surface, especially on the final cut. 0.010 to 0.015 of an inch is plenty.
2] When I have to have a long stem such as your valves, I will leave about 0.500" sticking out of the collet. Turn that portion to size and then pull the stock out another 0.500" and turn that portion to size. With a little practice you will be able to bring the tool bit to the first diameter and blend it in with the second diameter you have turned. When you get to the final cut for the second turning, you can put a piece of paper of a known thickness between the tool bit tip and the finished diameter that you want to blend into. As you move the tool bit in the paper will start to drag out of your hand. Then you will have a great indication on how close your tool bit is to the finished diameter.

Another trick is to put some layout die on the finished diameter and when you see a slight ring in the layout die, you know that you are there. A Sharpie marker will do the same thing.

You can use a real fine needle file and then some 400-600 grit sandpaper to blend any blemishes you might see. 

The basic idea is to use the stock as a support for you and leave the largest diameters to be turned closest to the collet or chuck. Once you have the stem turned and the angle machined, you can pull the the stock out and cut off your creation. Put the valve stem into the collet and face to size.

Keep up the great work my fellow budding model maker.

I hope I have not confused you because I am starting to confuse myself. I wish we were closer together and I could show you first hand. So much of machining becomes second nature that you really do not think about what you are doing. It just happens, so trying to put procedures into to words is kind of hard for me.


----------



## ShedBoy (Jun 5, 2011)

I have been giving HSS a go but having used carbides for so long it is hard to slow down. I have realised it is slower everything, speed, feed and cut. I am unsure of the material these valves are made of so I do not know if I have to harden them. I was going to turn some more out of some stainless. 
Brock


----------



## picclock (Jun 6, 2011)

Hi Shedboy
steamin's spot on with that info. The finishes you can get with HSS and a bit of lard are really good, if you want mirror you will have to use fine emery cloth and abrasive paste. 

For the diameter you are turning I would think the speed should not be a problem. As a conservative rough guide 50 fpm for normal low carbon type steels, which, assuming you have a work diameter of 1/4", means that for every revolution the tool cuts 3/4" (pi * D). So the speed ought to be (50*12)/0.75 -~ 800rpm. Unless you know the steel you are using its tricky to be accurate, but you could probably double that for most steels.

http://its.fvtc.edu/machshop2/Speeds/RPMcalc.htm gives some examples with a better calculating method.

Try using lard as a cutting lubricant - I've used it a lot and it works really well. Just have a small dish with a bit in and a scrap brush. Microwave it if its too thick. Paint it on before turning, with carbide or HSS. 

If you can get the required finish, and harden them with Kasenite or similar then the parts will probably be better than if made of stainless which has some issues.

Best Regards

picclock


----------



## metalmad (Jun 6, 2011)

Hi brock
 good going so far
with the valves I make them out of concrete fixing bolts and turn the 45 dregee angle of the valve near the chuck.
that way u only have the shaft coming out from there
makes it easy :big: 
Pete
Ps have a look at my posts Sows Ear /rattler and u will see its much better to have the big end near the chuck.
Pete


----------



## ShedBoy (Apr 11, 2012)

Well I found a container of small bits and after a mate laughing at me saying I never finish things I have made some progress. It is still going to be touch and go if it runs. 





Main frame coming together




The beginning of a cam gear












I made two of these just in case, it has one booboo on it but still useable for this engine




Started to make a crank gear out of some unknown material, big mistake. All was going well until about tooth 13 when some sparks come off the cutter and a split second later she stopped dead and made a orrible noise . After some thought I thinmk the material I grabbed was some caravan sway bar steel which was used for a job for the neighbour's rotary hoe, give me grief then too. One seriously blunt involute cutter was the outcome. Need to sharpen it some how.

Lesson learnt is know what you are cutting.

See you next week.

Brock


----------



## ShedBoy (Apr 21, 2012)

More work on this hideous thing




Bushed carrier for cam gear




Mounted on a shouldered stub bolted to the main frame




Cam made as described in topsy turvy plans but with ETW centaur measurements. Was easier than I thought




All pressed together interferance fit




Cap to hold it on which will be held with a set screw and will also be a pivot point for the governor arm. Maybe.




Beginnings of a flywheel, taper lock centre. I am starting to think maybe I nee a different cylinder and head.
Thanks for looking in.

Brock


----------



## Harold Lee (Apr 21, 2012)

ShedBoy  said:
			
		

> My crappy scribble plans got in a picture. Please ignore them.
> Brock



Brock - Looking real good!!!! And don't apologize for the scribble.... I adds to the whole build... Keep up the good work.

Harold


----------



## ShedBoy (Apr 23, 2012)

Thanks for the kind words Harold. Got some more done today




Got the taperlock made for the flywheel just need the tightening bolts and some jacking bolts then I can turn the rest of the flywheel on i a mandrel








Made the cam follower also today, used a small bearing for the roller




Fits in place well and has about 2mm of lift.
Still don't like the look of the cylinder :-\ got a piece of steel kicking around which may come into play.
Thanks for looking in.
Brock


----------



## Ken I (Apr 23, 2012)

Nice going so far Brock, just signing in to keep up with this tread, I want to see it run.

For what its worth high tensile bolts (hot / cold headed) make a good donor material for valves - especially since the upset grain flows into the head.

Beware work hardening steels - but I think you've found that out already.

Ken


----------



## ShedBoy (Apr 23, 2012)

Yes I did. Waiting on a new cutter but am going to try sharpening the dead one when I work out how it is done.

Brock


----------



## ShedBoy (Apr 24, 2012)

Made up a pushe rod for the cam follower and drilled the guide hole




Need to trim that block later after I work out the rocker support mount




I have decided to make another cylinder. This is the splined end from a large drive shaft from a CAT scraper 4140 I am told. Machines nice.




In the 4 jaw to get a flat to mount it. Lots of interupted cuts








Nice and shiny








Marked the centre of the bore and located it in the 4 jaw. Lots more interupted cuts. Had to stop as it was quite noisy at 10pm. More tomorrow then it is back to work. Thanks for looking in 
Brock


----------



## ShedBoy (Apr 25, 2012)

Got some more done on the cylinder
















Ended up with a 28mm bore. o.o1mm difference from one end to the other. I think it looks better than the other one.




I cast up some aluminium bar to make a piston, I have read in alot of plans to use cast bar for pistons, don't know why. Thanks for checking in, I will be back in the shed next week as I go off to work tomorrow 

Brock


----------



## ShedBoy (May 4, 2012)

Back from work so back to the shed, going to give it a good push this break. Here is the beginning of my porous piston. I really need to sort out my casting I think it was not hot enough or I need to get some flux of some kind, Maybe the oil burner is contaminating the melt. I have some ideas I am going to try.




Looks okay here




I am hoping this is not going to matter much here, can always make another if needed, I have seen worse in running engines




Better from a distance with a squint :big: :big: :big:




While in the tool draw on a totally unrelated mission I come accross my old brake cylinder hone which I forgot I had. As I am going to put a cast Iron ring/s in this engine I thought why not give it a hone to get a nice cross hatch pattern for the ring to bed into. Still got more to do. Finish the piston in the morning and make a start on the conrod and crank disc. Got a mates van sitting in my driveway which also needs to go back together (I hate working on vans with the engine under the seat) and going to see a bloke who is retiring and selling off his complete workshop, has all sorts of stuff and junk. 
Thanks for looking in.

Brock


----------



## ShedBoy (May 5, 2012)

Well the bloke who was retiring didn't want to sell anyhting but everything was for sale. Ended up with nothing but a 200km round trip, had a beautiful little shaper there to, oh well back to the dodgy engine.




Inside of piston done




Has a few oil holding pits in it but seals good with a couple of drops of oil just need to cut some rings




Taper lock drilled and tapped for flywheel




Able to turn between on a bit of shaft




Soldered on a crank disc and face it off. I have decided to use a shouldered bolt to hold on the big end so it is easy to keep square








It nows has a crank that turns. Going to make a crank gear in the morning followed by some rings. Thanks for looking in.

Brock


----------



## steamer (May 5, 2012)

I like the flywheel! :bow:

Dave


----------



## ShedBoy (May 5, 2012)

Thanx Dave,I was going to clean the sides up a bit more but it seems like it may ruin the theme I have going here :big: :big: :big:
Brock


----------



## vcutajar (May 5, 2012)

Brock

I have been following your build with interest and learning new things.

Not to pour water on a fire, but just a comment from an inexperienced model engine builder.

If you leave the lettering on the side of the flywheel aren't you increasing the chances of having an unbalanced flywheel? Or isn't this a problem at the relatively slow RPMs that we operate model engines?

Just a thought.

Vince


----------



## JorgensenSteam (May 5, 2012)

He could actually use the imbalance to offset the weight of the rod/piston, etc. and thus use the imbalance to his advantage.


----------



## ShedBoy (May 5, 2012)

Good point Vince. I will put it between some centres and see how bad it is.

Unicastings that made no sense to me and probably perfect sense to alot of people.

Looks like I need to look up some balance ideas. Should I mount the crank, flywheel, piston and rod between some centres and look for definate heavy spots and go from there? Does anyone have any idea how to balance this thing or should I just spin it in the lathe and see if it vibrates? Now I am confusing myself. Someone must have pics of balancing in progress.

Brock


----------



## ShedBoy (May 6, 2012)

Started making some rings today from some spun cast iron. I am using the method Bob described in his hit & miss thread









Thre rings cut and ready to split and finish to size. Got side tracked mid morning by a new tool.

Brock


----------



## Ken I (May 6, 2012)

Coming along nicely Brock.

I wouldn't worry too much about ballance for now - just keep it in mind for later.

Ken


----------



## ShedBoy (May 8, 2012)

Well me and piston rings don't get along. I think the material I have is not spun cast iron. I think a viton ring is looking good at the moment.












All three broke like that. I need to do some more research into ring making. I am going to make a crank pin and conrod instead before I go back to work tomorrow.
Brock


----------



## Blogwitch (May 9, 2012)

Brock,

Don't let things like this get you down, you are doing just great.

You have to learn to walk first, and when you have a little more time, you can spend it on making piston rings.

I have forgotten the number of rings I have broken over the years, and I used to make quite a few at one time.

Go with the Viton ring, get the engine running, and come back later if you feel the urge to fit a cast iron piston ring.

It is only yourself that is kicking you in the butt, everyone else is hanging on your every word because you are doing so well.


John


----------



## vcutajar (May 9, 2012)

hear hear.

We have a saying here which loosely translated says, "If you can't get through the door, then go through the window".

As John said the get it running and then if you want you can always come back and try again the rings. Personally if its running I wouldn't touch it again.

Vince


----------



## ShedBoy (May 20, 2012)

The pain continues with unidetified metals. But first a conrod




Piston on the rod with o-ring




This is the cylinder where it now lives and belongs. This was the spline end on a CAT scraper drive shaft it turns not to bad, a bit hard on tooling. When it come to drilling holes in it and then tapping it you have another whole set of issues. One broken drill and a blunt one later (one of the bits that snapped off lodged in the back of my finger at speed) the thing ended up in the bin. At this point I thought maybe they don't harden the part of the shaft which is not splined. I tried to cut it away from the splines on the left over shaft but after 30 seconds in the bandsaw I had removed the rust only. It is going to the scrap man. At this point the assembly of parts was put in a box and stored until a later date. The later date turned out to be the next day.




Cylinder #3, no complicate turning, easy fabrication coming.




Making the stand








Welding on the stand and squaring up. Back at the same stage.




First tool off the new grinder for cutting the valve seats




First valve seat cut beautiful, the second suffered act of zig when I should have zagged with the handwheels, one valve seat is alot widerr than the other but it should still work, if not I can fave the thing and make a valve cutter and recut the seats.




Machining the top of the head.

Brock


----------



## ShedBoy (May 20, 2012)

Head sitting on the cylinder, needs a plug hole.








Successfully eyeballed the plug into the right spot. Ignore the huge valve seat, I do.




This is where I finished last night, one machined valve guide. Now I am off to find some info on turning valves successfully. I have left the rest at the angle I turned the seats at. If anyone has a link or site they can point me to it would be good. Thanks for looking in.

Brock


----------



## Blogwitch (May 21, 2012)

Brock,

A simple way to cut valve seats is to use a 90 degree countersink tool in your tailstock, which is the angle that is required.

Take it steady to avoid chatter and they make a perfectly shaped valve seat. The rest is taken care of by grinding in.

John


----------



## ShedBoy (May 21, 2012)

I often thought about using one of them but was worried about getting it straight. The head is fine, it is the valves which I need to do now. If I need to take a skim off the head to narrow the valve seat I will give it a go. Turns out my con rod is too long also, I may just cut and weld it.
Brock


----------



## ShedBoy (May 23, 2012)

Well I have cut and welded the conrod to get the correct compression ratio I think (about 5.5 to 1) but now my piston comes out the bottom of the cylinder a bit to much for my liking :-\ I may just bore it out and put a cast iron sleeve in it with an extended skirt. The head now has ports drilled and is waiting on some valves. I have been a bit lazy on the photo front. I also made another crank gear as the first one did not get finished due to work hardening and wrecked involute cutter. I made one out of some stainless steel which cut like butter so I am assuming it is one of the nice grades, maybe 303.




Just need to drilled for a set screw and part it off. Back to work tomorrow :'(. Gives me time to relax and have a think. I think I am going to build from plans for the next engine as this measure and make system I am using with this engine is not the most effective way to use your time. I don't have meny parts left to go though. Thanks for checking in on the madness.
Brock


----------



## Ken I (May 23, 2012)

Just keep digging - the welded conrod gives me the heebies - I would make a new one once all the bugs are ironed out.

I design very thouroughly before making anything - the do it as you go or back of a fag packet approach invariably leads to trouble.

Its a lot easier to fix on paper (computer RAM - whatever) than in metal - and even then I've made some monumental errors (like a drive shaft going through another moving part of a machine and even gears that needed to go in opposite directions to each other.

As SWMBO says I'm just a man and can only juggle one thing in my mind at a time - two's a push.

Plan ahead.

Ken

PS Confucius says "Never look up at mountain - just keep digging !"


----------



## ShedBoy (May 24, 2012)

I had some thoughts on the welded conrod also and knew it would put some people off but I reckon 25mm of good weld will be stronger than two 4mm big end bolts under the same forces. I am sure someone good with numbers will chime in with some calculations. The rod is 10mm thick and was prepped with 4mm bevels all round then welded with a red hot Mig welder, I am confident it will be strong enough, but I will stand on the other side when I run it. I have nearly made every other part twice so it will probably get done. If I can get this thing to run on its own for a couple of minutes and maybe start a second time I am going to shelf it and move on. I really need to learn how to use some CAD software one of these days, it would make life alot easier. I know I am diggin myself into a hole but my work as an underground miner has prepared me for that, you can always go sideways and come out somewhere else and if you can't dig anymore blow something up :big:.

Brock


----------



## Ken I (May 24, 2012)

Can't fault your logic on the strength issue - But

(theres always a "but")

The root of a weld is always considered to be a crack (metalurgically speaking) and under cyclic loads cracks propogate.

Hence my comment about the heebies.

My concern would be related to long term use - its a small concern only FYI.

Ken


----------



## ShedBoy (Jun 1, 2012)

Back from work so back to the man cave. I have been dreading making valves again after my previous attempt. I have finished the gear for the crank just need to get some grub screws to lock it in.




Mesh is good for my first go at gears.




Inlet valve with 1 little booboo. I learnt from my mistake and aced the second. I am going to call it lightening, you'l see it




Should have faced the head off last on the first one. Live and learn Brock




Woohoo looks like valves and seal good so far, still need lapping in.




My lightening hole. I am telling myself it will be less weight for the vacuum to move :big: :big:




The dreaded head is nearly done. Now I have duties to perform which are not in the shed, DROLL. Will be back to it later today, I am told I will get early parole today. 

Brock


----------



## tvoght (Jun 1, 2012)

I'm watching this Brock. Moving at a good steady pace!


----------



## metalmad (Jun 2, 2012)

Hi Brock
looking good Mate
But If it was me, I'd be a little worried that valve has been badly weakend and if its the exhaust I'd definitely make a new one.
I normally make the exhaust a little thicker then the intake as its gunna take more punishment, especially if it runs as well as your last one did.
Pete


----------



## ShedBoy (Jun 2, 2012)

Gday Pete
It is the inlet valve and I have decided if it fires up I will make one to replace it, really getting sick of polishing this turd, I am just going to roll it in glitter. Worst part today was I went to get some grubs screws but they were shut for a stocktake  well back to the action.




Simple rocker stand




The rocker takes shape








I noticed some of these rockers in my scarp metal bucket, nice hardened pad on it. I had an idea form. Grinder time




I thought a hardened tip couldn't hurt








Silver solder away. Pad stayed hard, couldn't scratch it with a hacksaw.








Final shape and alignment, I am happy.




It all works as it should, ended up with 1.25 ratio rocker for about 2.3mm of lift. Should work okay. With no O ring on the piston there is a suction at the inlet port when you spin it with the drill but I need a stronger exhaust spring. Thanx for looking in.

Brock


----------



## steamer (Jun 2, 2012)

Looking great Brock!  

Dave


----------



## ShedBoy (Jun 4, 2012)

Been plodding along and kicking some goals





Igniton breaker cam




Exhaust pipe and inlet stub which needs shortening




The start of a carby, took some inspiration from Chuck's carb he is building at the moment




Made a intake venturi to make it pretty, this engine needs some bling. 6mm hole through the middle
















The spray bar forms the venturi in the carb (Thanx for the idea Mr Fellows) The problem was soldering it together and not getting any solder in the cross hole which was drilled before hand. More to come.
Brock


----------



## ShedBoy (Jun 4, 2012)

Cue the Liquid Paper/ White out, flux and silver solder add heat until combined




Stop, pickle time 




The general gist of it




Three different size holes to three different depths. This is the last hole 1mm for 3mm. The problem is you can't tell if you snap it off as it is so small (well it is for a ham fisted oaf like me, thankfully it came out the same length it started at.




This is the set of drills I got for this job, $2.95 from Jaycar Electronics. The are PCB drills and look good when magnified.




Needle end is done




Other end was drilled for fuel supply. I have found a needle to try. Today I am going to finish the carb, only 4 simple parts to go and mount the points. May even pull it all apart and do some final assembly  It is getting exciting. Thanx for checking in.
Brock


----------



## ShedBoy (Jun 5, 2012)

Got more done today




Finally used my knurling tool




Little drills scare me




Needle finished




Needle in carb








Last machining on carb body




Just need some gland packing




Pic of the air screw




Lever to lock in position and soldered onto stub.




Group shot. After this pic I mounted the points and painted the main frame and cylinder, not much to go now.
1. Lap in valves
2. Space out O ring with some ali can or foil as it misses by 0.2mm but good sign it has compression.
3. Make some sort of base, chunk of wood.
4. Make 3 gaskets
5. Drop parts it ultrasonic cleaner for a bit
6. Bolt it together.
7. Wire it up, add fuel and give it a spin

Hopefully this time tomorrow we have had some pops, fingers crossed. 
What would I use for gland packing on the needle?


Brock


----------



## ProdEng (Jun 5, 2012)

Look forward to hearing your engine make some noise! The Jaycar tip is a good one, have to get some of those 

Jan


----------



## danstir (Jun 5, 2012)

Great build!! Looking forward to hearing it run. Thanks for sharing.


----------



## tvoght (Jun 5, 2012)

That carb looks cool. And the braze looks excellent!

--Tim


----------



## ShedBoy (Jun 6, 2012)

IT RUNS, unbelievable. I took some video of it but my can't get sound on computer. There is sound on the camera though. I am stoked. The carb needs some sorting but that was to be expected. It runs hot real quick but it runs need a model engine to start it but the revs are quite low. Dam camera. Might have another go later. Video with no sound here
http://s1080.photobucket.com/albums/j325/brockster13/Engine 1/?action=view&current=SAM_0202.mp4

 8) It is done

Need to make a new needle but have to go to work tomorrow :'( just when it is getting exciting.

Brock


----------



## ShedBoy (Jun 6, 2012)

Turns out the sound works on photobucket.

Brock


----------



## ProdEng (Jun 6, 2012)

Congratulations, that sounds great and with a bit of tuning will be a winner. :bow:


Jan


----------



## vcutajar (Jun 6, 2012)

Congrats Brock on your first engine. Even by reading your post you sounded very excited and happy.

Now to finish my first engine.

Vince


----------



## tvoght (Jun 6, 2012)

Wow! Sounds and looks great!

--TIm


----------



## metalmad (Jun 6, 2012)

great going Mate
congrats on first pop ;D
pete


----------



## mzetati (Jun 6, 2012)

Well done, Brock!
And a nice build thread.

Marcello


----------



## Blogwitch (Jun 6, 2012)

Isn't it a good feeling hearing that 'pop' for the first time?

And I wouldn't mind putting a bet on that you got just as much enjoyment from making it out of old bits and pieces rather than it costing you hundreds of bucks for a casting kit.

Keep that grin on your face for a while yet, and get it running continuously.

Very well done indeed. :bow: :bow: :bow:


John


----------



## b.lindsey (Jun 6, 2012)

Congratulations Brock...and thanks for letting us ride along!!

Bill


----------



## ShedBoy (Jun 7, 2012)

I had to run it again for her indoors last night when she finished work and was able to get it to run for about 30 seconds.
Brock


----------



## dgjessing (Jun 7, 2012)

Excellent! :bow:


----------



## fcheslop (Jun 12, 2012)

Congratulations Brock and thanks for the journey 
best wishes Frazer


----------

