# Potty Popcorn Engine



## SBWHART (Sep 20, 2011)

Well I had a desaster on my Loco work I chipped a chunk out of the wheel flange its totaly US, this realy pissed me off I've consigned the loco under the bench whilst i get over my sulk, I'll just have to buy a new wheel.

In the mean time I decided to get on and do a bit on this.

Her's the assy drg







I showed the fly wheel build on another thread her's a pic of it






I was planning to fabiricate the cylinder in three parts but then I found I chunk of 1 1/2" square brass left over from the loc chimney, I realised that I could make the cylinder in one peice from this.

So marked it out and set it up in the four jaw.






Drilled and reamed the bore out 1/2" then turned a mandrell up for it to fit on.






With this in the spin-indexer milled the cylinder to shape.






Then milled the steam ports






So that I ended up with this






Cylinder covers

One thing a beginner struggles with is lack of kit for drilling holes on a pitch circle.

Well if you have one of those digital protractors you can use it to acuratly mark out the holes.

With the bar in the lathe
First put a small centre into the bar then using a pair of deviders mark the circle in the end of the bar.

Then zero the protractor up on the bed of the lathe, put the protractor on the chuck jaw, rotate to get it zero, then mark across the bar with a scribbing block, rotate the chuck until the protractor is showing 90 deg mark across again, job done.






Centre pop and drill holes






I decided that I would like something fancy on the cover, so with the chuck mounted on the spin indexer and with a vee shape fly cutter form a star in the end.











That doesn't look bad.

Stew


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## steamer (Sep 20, 2011)

Actually I like that a lot Stew!

Dave


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## Brian Rupnow (Sep 20, 2011)

Stew---You are my new hero!! You do lovely work. ---Brian


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## metalmad (Sep 20, 2011)

Thats a great idea!
I love it, Pete


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## bearcar1 (Sep 20, 2011)

Yeah but how'd you bust the wheel?  ??? :hDe: 

Sorry Stew, I do not mean to scratch an old scab. Terrific job on the cylinder and cover. Me likes alot!!

BC1
Jim


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## larry1 (Sep 20, 2011)

Stew, Great job.  larry


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## Deanofid (Sep 20, 2011)

Looking great, Stew. You do nice work!


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## tel (Sep 21, 2011)

Looking good Stew - off to a flying start on another masterpiece!


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## jonesie (Sep 21, 2011)

looking good stew, sorry about your wheel. thanks for the pdf files they look good after a quick look. i am also going to make the cylinder from one piece, but i think i will start with the flywheel. i will try to post pics as i go but need to finish up a couple projects, need to get my farmboy running for a local show then on to the popcorn. thanks again for the files jonesie


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## SBWHART (Sep 23, 2011)

Thanks for your support chaps

Good luck with your build jonesie, any problems with the drawings just send me a PM

If anyone else wants a free copy of the drawing just send me a PM with your email adress, but I must warn you they are untested so their will be mistakes.

Got on with making the valve chest, this was fabricated and silver soldered, I used some hex bar fly cut down to size.






The bits for soldering I losely pined together with 1/16" brazing rod






And soldered together






I squared the fabricarion up as you would a casting, then centre drilled for the valve rod position, and set it up in the four jaw with a wobble bar






Drilled it through 3mm then drilled and tapped 1/4* 32*8mm deep

Marked out for the bolt holes drilled these through 3mm then used the chest as a jig to spot through and drill and tap the cylinder, and drill the cover 3mm.







Slide valve milled a bit of brass to size and milled the vlave pocket in the base flipped it over and milled the cross slot for the rod and cross bar.











These are the bit for assy.






Slide valve in the chest.











That valve cover is just calling out for something.

Stew


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## lazylathe (Sep 23, 2011)

Awesome stuff as usual Stew!!!!

This is going to be another winner!!!!!!!!!!

Andrew


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## tel (Sep 23, 2011)

> If anyone else wants a free copy of the drawing just send me a PM with your email adress, but I must warn you they are untested so their will be mistakes.



Put me on the list please matey.


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## SBWHART (Sep 24, 2011)

Thanks for you're interest Guys.


Added a bit of fancy work to the steam chest cover, its a bit flimsy to grip so soft soldered it to a chunk of brass, centering it by eye.






Then over onto the spin indexer, centred the tool again by eye, you don't do the cuts on centre you off set it a bit, to cut the star .






Gave it a bit of heat to melt it off the solder, and a clean and polish.

That looks better.






Made a start on the piston, turned the piston up from a bit of stainless steel:- thanks Dave :thumbup:, made it about 0.3mm over size, and put a groove in it for the packing, parted it off, and screwed it onto the rod with studlock, I'll give it a bit of time to cure before I bring it down to size.







Stew


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## Brian Rupnow (Sep 24, 2011)

Stew---if you would be so kind as to send me a set of the prints, I would be very gratefull. If you click on the link to my web page, all of my contact information is there. Thank You----Brian


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## ShedBoy (Sep 24, 2011)

Great start there Stew. Those little stars look a little like a compass symbol. Looks great.
I will be watching


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## Brian Rupnow (Sep 24, 2011)

Stew---Thank you for the drawings. They are very well done. Did you have formal training as a draftsman at some point in your career? It has been my experience that most good machinists don't make mechanical drawings, and most mechanical draftsmen don't machine.--And, out of curiosity---How is the crosshead guide attached to the cylinder cap?----Brian


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## tel (Sep 24, 2011)

They are very nice drawings, and more in line with what us old school ME's (dinosaurs) are used to!

A pox on CAD, and all who sail in her!


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## Brian Rupnow (Sep 24, 2011)

Tel---Up untill I was 50 years old, I wholeheartedly agreed with you. I loved working on the drafting board. At 50 I had been doing so for 31 years, and I was damn good at it. Computers, CAD---who needed it. Then suddenly reality jumped up and bit me on the ankle. Nobody wanted to do business with me unless I could churn out amazing designs on a computer. Drafting board was equated with "Horse and buggy!!!"---If you couldn't do it on a computer, then you must be far to "old school" to design NEW IMPRESSIVE WHIZ-BANGS for your customer. So at 50 I went creeping back to college to learn Autocad. It wasn't that terribly difficult---but after 3 years, just as I was starting to get good at that, suddenly the customers wanted 3D, with animations, and "full associativity" (whatever the heck that is.) So off I went to learn 3D Solidworks. To make a long story short, I am amazed and impressed daily by what I can do now on my computer with CAD, and so are my customer base.----But---- deep in my heart of hearts I'd still like to be perched on a drafting stool, a cigarette in one hand and my trusty 2H pencil in the other, flogging lines onto an E size vellum, with my squeaky old Keuffel & Esser parallel track drafting machine.


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## Tin Falcon (Sep 24, 2011)

> It has been my experience that most good machinists don't make mechanical drawings, and most mechanical draftsmen don't machine.-


Well Brian am a little younger than you my first mechanical drawing classes were in Jr High then in high school. I learned to hate drawing title blocks over and over also the repeated hand lettering. 
never really did the autocad much a tad bit in college. But when I took my USAF machinist courses bit later in life we had to learn a little mechanical drawing . 
I sit here at my Oak Mayline drafting table and type on the laptop loaded with alibre 3-D the drafting arm behind the CNC control computer there are still a few lead holders in the carousel near by. 
Tin


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## Maryak (Sep 24, 2011)

Brian,

Anybody who can produce a set of drawings using a drafting board etc., has my utmost admiration. If you have the misfortune to be like me, then CAD is a godsend because a well used flypaper, complete with dead flies, was far more presentable than my hand drawn efforts.

Apologies for the hijack of the thread.

Best Regards
Bob


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## SBWHART (Sep 25, 2011)

Thanks for your positive support chaps



> Stew---Thank you for the drawings. They are very well done. Did you have formal training as a draftsman at some point in your career? It has been my experience that most good machinists don't make mechanical drawings, and most mechanical draftsmen don't machine.--And, out of curiosity---How is the crosshead guide attached to the cylinder cap?----Brian



Brain:- I had what I suppose you would call a technical education, I did some tech drawing at what we called secondry school (up to age 15) then I did a 5 year apprenticeship and took city and guilds and a Higher National Cert in engineering at day release and night school, that had an element of drawing practice, a few years ago I went back to night school and did a basic autocad course just out of interest, never got as far as the 3D cad,
Before that I did a degree in science and technology with the Open University (home study), I chose units that had a high level of engineering design and technology, by far my favourate unit was on the history of the Industrial Revolution in the UK, it went into why it came about. I also earned a living as a project engineer in a design department, my wife recons that I never really retired, that I just carried on my work as a hobby :-\

Between you and me, I've got a bit of a blind spot when it comes to 1st and 2nd projection I get them mixed up.

The cross head is just a tight fit on the steam chest cover (cylinder cap) at the front end it fastens to the crank shaft bearing support, trapped between these two parts it can't go any ware, you can see this set up on the full size engine but with them, the end turns through 90 deg to bolt onto the bearing support, this would have bin difficult to reporoduce in bar stock.

Thaks for you interest guys.

Stew


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## SBWHART (Sep 25, 2011)

I've got no pics of this mornings work, I just finishing off the piston and tidied a few things up. I took delivery of a length of 3/8" hex yesterday so I made the gland nuts, for you guys who I've sent drawings to I changed these some what, I decided that as drawn they looked out of proportion, so shortenend the length of thread by 2mm and the thickness of the head by 2mm.

I've realy bin pleasantly suprized by how many have asked for the drawings and the reaction to them, thanks a bundle Guys. My reason for sending them out and not posting them for download was:- I new I would make changes, and I wanted to stay in touch with the people who had them so I could send them the updated drawing pack, I also thought it would be a good way to get them proof read.

I intend to draw up a valve, displacement lubricator, and governor for it, but I won't do that until I've got the engine completed, so that I can get an idea of proportions and how things will fit together.

Thanks again for you support

Stew


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## jonesie (Sep 25, 2011)

thanks stew for the change update, getting stuff ready to start flywheel. looks like you are making good headway. i changed the number to english as all my tools are that. thanks again,yours is looging good jonesie


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## Brian Rupnow (Sep 25, 2011)

Stew---you definitly get Karma for being brave enough to post your drawings and for doing such amazing work. All the rest of you chaps who are following Stews work or downloading or being sent his drawings---give Stew a Karma by clicking his applaud button. If you had to pay out of pocket for his designs, You would be paying from $20 to $50.00. Stew can't spend his Karma, but it will give him a sense of how much we appreciate what he is doing.----Brian


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## ozzie46 (Sep 25, 2011)

Received the plans. Thanks again Stew.


  Ron


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## steamer (Sep 25, 2011)

Hey Stew,
As you requested, I've given the drawings a once over....OK maybe a two or three times over... ;D

What I found was small....but I did find some stuff.

Page 1 ....GA   clean

Page 2.....zone D7  The bore dimension of the hub is missing ..I assume it's 4mm.

page 3....clean

page 4....clean

page 5.....zone C4  A dimension is required from the centerline to one side of the 10mm wide centerline web
       Zone B6-B7  A thread callout for the ends of the pistion rod....I assume M4.
       zone D4  Missing diameter call out for the bearing diameter of the pin  I assume it's 5mm?

page 6.... zone C3  Part 21, The dimension is missing on the pad that forms the mount for the crosshead guide. I assume its
              2mm deep or 6 mm from the backside....
       zone A7  The crank pin diameter is missing...I assume it's 4mm?

Lastly....a request from me.  On page 4 add a pair of M2 screws to hold the steam chest in place while the valve is being set.
When I built Rudy's "Little Work Horse"....which was an identical chest design, it was a pain to get the chest to line up again once you were ready to put the cover back one. I added a couple of screws on the chest only to hold it in place while the cover was off. The steam chest cover , covers those screws once assembled.....however this is a very minor point.

I like the design alot!  To me is screams for a small generator to sit between the bearing journals! Can't wait for the governer!..... ;D

And some Karma from me too!

Dave


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## tel (Sep 25, 2011)

> Lastly....a request from me.  On page 4 add a pair of M2 screws to hold the steam chest in place while the valve is being set.
> When I built Rudy's "Little Work Horse"....which was an identical chest design, it was a pain to get the chest to line up again once you were ready to put the cover back one. I added a couple of screws on the chest only to hold it in place while the cover was off. The steam chest cover , covers those screws once assembled.....however this is a very minor point.



Which is why I almost alluz fit the steam chest with studs!

Karma from me as well Stew!


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## steamer (Sep 25, 2011)

That would do it too Tel!
Dave


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## Brian Rupnow (Sep 25, 2011)

I feel a bit foolish for asking----But why is it a "Popcorn" engine. I know about old time pop corn vendors having a steam driven engine on their "Popcorn wagons" to turn the drum of popping corn, but you write in your drawing that this is a 1/3 scale model. Was the original "Popcorn engine" really 3 times bigger than what you have designed?


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## steamer (Sep 25, 2011)

Hey Brian,

YUP  about 1/3 size of a Cretors

http://www.myersengines.com/engines/popcorn_engine.htm

Cretors used mild steel on the governer valve spool which results in the valve sticking shut after some period of non use and results in the 17 something year old operators looking dumb founded as to why it won't work even when the safety is popping off resulting in the Chief to tell his Volunteer Engineer to take it off! "Damn thing!"  Works well if you use it every day....but don't let it sit!

Make the governer parts out of bronze or stainless please............ ;D

Dave


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## Tin Falcon (Sep 25, 2011)

http://www.cretors.com/page.asp?i=12#1880 the old cretors wouls roast coffe , peanuts and chestnuts as well as pop corn.
Tin


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## SBWHART (Sep 26, 2011)

Thanks for the Kalma's Guys

Thanks for the proof read Dave I've penceled the changes in on my working drawings I'll catch up with the cad changes later.

I do the same as Tel and fit studs, but I had noticed on pictures of the engines that they nearly always use slotted screws, so figgure I could just use a couple of shortend bolts to hold things down while I set the timimg.

Thanks for the info on the governor:- Bronze and stainless it is then.

I guess some of you Guys are wondering how a Limey knows about popcorn engines, well you can blame Bogs for that one, he showed me some drawings he had for a wobbler type popcorn engine, that got me thinking, did a little reasearch and found pictures of the Creaters and Dunbar slide valve engines, they looked interesting and their aplication is unusual for the UK, and I like the unusual.

Stew


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## SBWHART (Sep 26, 2011)

Made a start on the cross head guide bar, I'm using a bit of 32mm dia free cutting mild steel, but aluminium could be used if you wish.

This is the type of job you have to think through to get the correct machining sequence, the important features are the 16mm bore that the cross head works in and its concentricity to the 24mm counter bore that the front cylinder cover fits on, this will keep the cross head centre line on the same centre line as the cylinder bore.

First op centre drill and turn down the 24mm diameter,







As the wall thickness at this end will only be 2mm I wanted to drill the 20mm as the last op, so I put down a 3/8" pilot drill followed by 1/2" roughing drill. For these drilling operation I had to support the front of the bar with a fixed steady.






Flip the bar round, and face to length and turn 28mm dia. 






I was strugling to get enough reach on the tail stop over the top of the saddle, so I though if a take the sadle off I'll get closer, then I though, no if I take the tail stop of and put it in front of the sadle that would be a lot easyer.






Drilled with a searise of drill finished drilled the 20mm dia, then put a 15.5 mm drill through, and finshed of the cross head dia with a 5/8" reamer, I was real lucky that I hade thease sizes amongs my limited selection of larger drills and reamers. I was planning on boring this dia out but I hadn't got a boring bar that long, and if I had it would be a dificult job, being on the long side to get a good result, if you havn't got a reamer a drill with corner slightly radiused would do the job, the size is not that critical you can make the cross head to fit. 

Bored the 24mm counterbore a nice push fit on the front cover.






As these two critical feature were finished at the same setting they should be nice and concentric.

Swap it round the other way and finish the other end off with a 20mm drill to depth.

Her it is on the cylinder.






Tomorrow I'll mill it to its final shape.

Stew


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## jonesie (Sep 26, 2011)

will add the changes to my prints. a karma from me also jonesie


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## Tin Falcon (Sep 26, 2011)

Stew:
thanks for the plans. Have not had a chance to open and print yet. MRS Tin and I share the computer with the e mail on and work has been crazy feels like we need a month to finish out the last week of the month. 
Tin


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## cfellows (Sep 26, 2011)

Nice progress, Stew. I'm very interested in seeing how the crosshead guide turns out. I've always admired the style of crosshead guide used on the Cretors popcorn engine but never took the time to figure out how to machine a replica. Give us some nice pictures... 

Chuck


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## SBWHART (Sep 27, 2011)

Thanks for your interest Chuck

For some reason I had it in my head that this type of cross head guide was vee shaped couldn't work out how they made them figgured that they used a big slotter. Then last month we visited the Northern Mill Engine Society running day in Bolton http://www.nmes.org/ they have a number of horizontal their that you can get up close and have a good study, it was then that I relaised that they were round, this opened up the posibility for making one.

Her's a pic of a cross compound, with corless valve, I was mesmerised by their action just like the guy lady in the shot.







I keep pondering on how to model a corless valve set up.

Stew

Stew


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## SBWHART (Sep 28, 2011)

> I'm very interested in seeing how the crosshead guide turns out. I've always admired the style of crosshead guide used on the Cretors popcorn engine but never took the time to figure out how to machine a replica. Give us some nice pictures...




Ok Chuck plenty of pics it is then.

Before milling the guide out I had a little corrective work to do, when I did the lose assembly I found that the nuts on the cylinder cover stopped the guide sitting down, so I set it back up in the lathe and cut the 24mm dia 2mm deeper.

To Mill out

First up I blued the guide up and using the spin-idexer marked it out, and cross hatched the bits to cut away.

Milling it out doesn't call for exact presision, you're trying to get a neat visual effect, the origonals were cast so they would have had inperfections.






On the mill first mill across the end keeping it short of the corner, this is so I would have room to run the cutter and take advatage of the horizontal power feed,.






Then mill down to the line.






Using a 14mm dia ball nosed cutter clean out the corner.






Now I had a nice flat platform to sit on to do the other side.






I swung the vice round 90 deg again so I could take advatage of the power feed, and milled out 68mm gap. For some time I was trying to figure out the best way to grip the job to machine the 10mm wide support, that bolts to the bearing stand, whilst doing this op I realised that the solution was stearing me in the face, all I had to do was mill into the the edge until it cut through into the bore.






So that you have this.






It is now a simple matter to use an hack saw to finish the job off.






1/2 hr work with files to blend every thing in and you have this.











Its not quite finished yet I'm unshure how the crank will clear the end of the Guid I may have to but a dog leg bend in it, I'm going to leave this untill I've got more bits arround me.

I didn't quite get the depth of some of the drilled holes correct I was short from both ends with both the 20mm holes don't know what I did wrong probably a maths error. but it won't be any detriment in fact it will just mean the cross head will be supported over a longer distance.

Stew


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## Lesmo (Sep 28, 2011)

Just caught up with this one Stew, after a fortnight away in sunny Devon, and I have to say it I like what I see. Its up to your usual high standard and if it runs anything like that beautiful Overcrank you built (which I am still dreaming about building) we will all be well pleased.

Do you have a link to the flywheel thread you referred to, I am fascinated to see how you achieved that spoke detail. Keep up the good work. Oh yes, and Karma from me too

Les


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## SBWHART (Sep 28, 2011)

Hi Les

Hope you enjoyed your Devon holiday, I like that part of the worls myself, and thanks for your kind comments.

You will find the flywheel her

.http://www.homemodelenginemachinist.com/index.php?topic=15650.0

Stew


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## Brian Rupnow (Sep 28, 2011)

So Stew---How did you put in that 20mm radius that shows in the plans? did you just sawcut with the hacksaw and then file the radius in?


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## SBWHART (Sep 28, 2011)

Hi Brian

Yes a just hacksawed and filed to eye. A feature like that is mainly for appearances as long as it look OK then it is OK.

Stew


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## Brian Rupnow (Sep 28, 2011)

Stewart---I wish I knew someone like you on my side of the atlantic, close enough to visit with. I am fascinated by what you do, and the wealth of knowledge you display while doing it. I am more or less the "King of the hill" in my area when it comes to model engineering, and I am only too well aware of my failings. It would be so nice to have someone who knows more than I do close enough at hand to visit their shop and "pick their brains" when I am left puzzled by things that should work, but due to some error of mine won't work. I know that this forum helps a great deal with those situations, but its not quite the same.---Brian


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## Blogwitch (Sep 28, 2011)

Methinks I am the lucky one, Stew only left my house fifteen minutes ago. He lives about 20 minutes walk away.

Not only do we share knowledge, but tooling, and even machinery at times.

I actually don't need to look at this post, as Stew brings the bits around to show me in person.

Two minds are always better than one, that is why I have an open workshop, you never know who is going to turn up next to help you out, or seeking assistance.

But we are very lucky in the UK, engineering is in our blood, and down almost every street, you will find people knocking up bits and pieces in their sheds and workshops.

John


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## Brian Rupnow (Sep 28, 2011)

You are indeed a fortunate man John. Model engineering types are few and far between over here.


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## fcheslop (Sep 28, 2011)

Hi Stew,many thanks for taking the time and effort to post you're build I'm really enjoying it.
best wishes Frazer


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## Brian Rupnow (Sep 28, 2011)

Stew---I am going through your drawings and "proofing" them as I model them. A couple of things I have noticed---#1-there is no dimension for the boss diameter on the side of the Front Cylinder Cover that faces away from the cylinder. #2--No height is given for the base, although a little trigonometry shows it to be 14mm high. #3--No location is given on the cylinder drawing for the 3mm dia. exhaust port. We know it is centered between the two ends, but not how far offset it is sideways from the cylinder bore. #4--Although it shows the port extending from the 3mm inlet port down into the cylinder bore at the ends of the cylinder, no dimensional information is given on it. #5-What is the diameter of the recessed area in the center of the piston? These are not criticisms in any way. Its just that someone setting out to build this engine may be a bit confused without that information.


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## Brian Rupnow (Sep 28, 2011)

Unless I've done something terribly wrong, there is going to be an interferance between the inside 20mm dia of the crosshead guide and the bolts which hold the cyl. front cover on. Methinks that 24mm dia. x 3.5 deep counterbore in the end of the crosshead will have to be about 5 mm deeper.


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## tel (Sep 28, 2011)

It's always going to be tight with the cover bolts inside the crosshead guide like that. T'were me, I would be moving them to the outside, to pick up the cover and the crosshead guide with one lot of bolts - as I did in this somewhat similar set-up. Apologies for the lousy paint job!


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## Brian Rupnow (Sep 28, 2011)

Actually the crosshead guide will work as detailed by Stew---IF--you use socket hd. capscrews and c'bore the cyl head for them. Now---A little trick here. Stew has designed this engine in metric. I am sticking faithfully to Stews drawings, except in the area of fasteners. Stew uses M3 metric fasteners. I am using #5-40 fasteners which are 1/8" o.d., which is as close as damn is to to swearing to a 3mm dia. fastener. And I will alter the bore of the cylinder to 1/2", which is 12.7mm instead of Stews 13mm bore.


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## Brian Rupnow (Sep 28, 2011)

Stew---I'm modelling your Popcorn engine, but I don't want to flood your thread with 3D models. Would you rather that I start a seperate thread to show the modelling of it?----Brian


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## tel (Sep 28, 2011)

> Actually the crosshead guide will work as detailed by Stew---IF--you use socket hd. capscrews and c'bore the cyl head for them.



No offense, 'cos I know you love 'em, but slotted cheese heads might be more in keeping with the original. You can do the same with those.


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## steamer (Sep 28, 2011)

Nice looking engine Tel!

Dave


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## SBWHART (Sep 29, 2011)

Brian:-

No problems with you posting her, and thanks for the proof read

To answer your ?


#1-there is no dimension for the boss diameter on the side of the Front Cylinder Cover that faces away from the cylinder. 

I made it 10mm

 #2--No height is given for the base, although a little trigonometry shows it to be 14mm high.

I deliberatly left it off I was going to add a not to say adjust on assembly to bring cylinder centre line onto crank shaft centre line.

 #3--No location is given on the cylinder drawing for the 3mm dia. exhaust port. We know it is centered between the two ends, but not how far offset it is sideways from the cylinder bore.

Its 5mm

Exta note:- the slot drills I used to cut the port would not cut to the full depth, what I did was chain drill the ports with nearest undersize number drill to 6mm deep, they broke into each other and I mashed them up a bit with a screw driver so that they joined up, then I finished them off with the slot drill. Its only the very lip of the port thats functional, the rest is just air pasage, and the air won't know if its a bit roughed up.

 #4--Although it shows the port extending from the 3mm inlet port down into the cylinder bore at the ends of the cylinder, no dimensional information is given on it.

Its 3mm wide by 2mm deep but its not that important it can be filed, I also like to chamfer the edge of this feature so that the piston packing doesn't catch on assembly.

 #5-What is the diameter of the recessed area in the center of the piston? These are not criticisms in any way. Its just that someone setting out to build this engine may be a bit confused without that information.

I'm going to use graphite packing so i made it 1.5 deep Ie root dia 12mm, I'm planning on putting a note saying "a suitable O ring may be used" so these feature will have to match the O ring.

#6 Unless I've done something terribly wrong, there is going to be an interferance between the inside 20mm dia of the crosshead guide and the bolts which hold the cyl. front cover on. Methinks that 24mm dia. x 3.5 deep counterbore in the end of the crosshead will have to be about 5 mm deeper.

I did come across this I simply cut the hole deeper to 5.5mm and widend the web on the outside the same amount. You can see the pencil change here.






Just a few other things I actualy made the bore 1/2" thats what size reamer I had, I've also added an extra tapped hole in the base of the cylinder to screw the base onto its inbetween the two holes already shown and is the same size, likewise I've added the hole to the base countersunk to take a cap screw head.

I'm concerned that the cross head guide will foul with the crank web, if it does i will have to put a dog leg bend in the 10mm wide bit of the guide, you 3D model may show this up.

As you may have noticed I do change thing as I go along to suite what kit and material I have, and my whyms.

Thanks for all your interest Chaps

Stew


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## SBWHART (Sep 29, 2011)

I measured the bore up as carefully as I could and as far as I can tell its got a 0.05mm taper in it being smaller at the front, I reckon I can live with that.

Made the cross head this morning, started with a chunk of brass in the lathe turned the bore down to a nice fit in the guide, and drilled and tapped it M4, 






Then keeping the job on the chuck transfered it over to the spin-indexer, zeroed the mill up on its centre line, and fly cut down one side.

Before milling down the other side, drilled through 3mm dia then using a 10mm slot drill cut down 7mm, the extra thickness kept everything nice and strong.






Index 180 and mill the other side to give a thickness of 10mm.

With it still retained on the chuck transfer over to the lathe and part off.






Set up in the mill vice and cut out the throat to give clearance to the connecting rod, flaring the throat with files.






Finished cross head fitted it's a little tight towards the front but that will run in.






One last job this morning the cross head pin a straight forward turning job.

Her it is fitted.







Stew


----------



## Brian Rupnow (Sep 29, 2011)

Stew---Does this look reasonable so far?--I wasn't sure if the flanges on the crankshaft bushings faced the way I have shown them.


----------



## SBWHART (Sep 29, 2011)

Wow Brian that looks very good.

Yes flanges are the way I was planning to mount them.

Stew


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## Brian Rupnow (Sep 29, 2011)

Stewart---As I get into this a bit deeper---Your cylinder is 32mm long face to face. The cyl end caps intrude into the bore 1mm at each end, leaving 30mm inside the faces of the endcaps. The piston is 5mm long, and the throw on your crankshaft is 12.5mm. This leaves absolutely no clearance at the end of the piston in either direction. Is this what you intended. The only saving grace would be a 1/2mm thick gasket under each cylinder cap.---Brian


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## SBWHART (Sep 29, 2011)

Hi Brian

I've made the cylinder 2mm longer than the drawing as I thought things looked a bit close, so I sould be OK.

Thanks for picking this up the other guys following this should take note also.

Stew


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## Brian Rupnow (Sep 29, 2011)

Thats about as far as I can take the modelling at this point. Looks great, doesn't it!!!


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## SBWHART (Sep 29, 2011)

Looking very good Brian great Job :bow:

Stew


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## Brian Rupnow (Sep 29, 2011)

Stew---Based on your original drawing of the crosshead guide, a 12.5mm crank throw, a 68 c/c piston rod, a 5mm thick piston, and a 34mm long cylinder, this is the way the centers work out. It looks good and everything appears to clear, but the crosshead comes out of the crosshead guide by about 4mm at end of stroke. Is this acceptable?






View attachment POPCORN ASSEMBLY.PDF


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## SBWHART (Sep 29, 2011)

Hi Brian

As I've made it the cross head will be within the guide I made a mistake with the hole depth for some reason or other probably a maths error by me.

But I wouldn't think it would mater that much it still got plenty of support and it also gives the connecting rod a bit of clearance when its at mid stroke.

That crank/rod clearance looks OK if it is a problem I can always file a small flat on the connecting rod and blend things in.

Bin working on the rod tonight whilst its cool, its bin a scorcher today in the UK.

The drawing realy are looking great.

Stew


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## Brian Rupnow (Sep 29, 2011)

Okay Stew---I've bothered you enough. I have your Popcorn engine fully modelled now, using metric dimensions everywhere except for bolt sizes which are practically the same diameter anyways, and for shaft sizes, where I have standardized on 1/8", 3/16", and 5/16". Unfortunately there are no British Imperial size shafting that corresponds to 4mm, so I bumped the 4mm shafting up to 3/16" which is 4.76mm. I used a 1/2" bore because I have a 1/2" reamer, and the bore inside the crosshead guide (and the crosshead itself) got bumped to 5/8" because I have a 5/8" reamer. Thank you for your patience. I will wait now to see your completed build, and the next time I feel an urge to do some work in my little shop I will probably build a clone of your engine with British Imperial dimensions. One nice thing about the computer is that I can model everything in metric, then have it generate drawings with all of the metric converted (Hard conversion) to British Imperial to 3 decimel places. Thanks again.----Brian


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## Dan Rowe (Sep 29, 2011)

Stew,
I have been watching this with great interest especially how you attached the frame to the cylinder head. What type of fastner is used for the joint?

The engine looks very much like the early Shay cylinders. 

Dan


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## SBWHART (Sep 29, 2011)

Hi Dan

Its just a push fit onto the front of the cylinder cover, the front of the frame is bolted to the crank saft bearing frame, holding it in place.

The cylinder cover is bolted to the cylinder with M3 bolts.

Hope this makes sence.

Thanks for you're interest.

Stew


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## SBWHART (Sep 30, 2011)

On with the connecting Rod:-

Cut a length of mild steel to length and put a sacrificial centre in each end.

Then with the compound set over at 2.5 deg for the barrel shape






Then onto the mill and mill flats on the ends had to use thin parallels for the barrel to fit in.






Drill holes for the bearings






This is what you get






Cut the centers off then using filing buttons shape the eye at one end to fit in cross head.






It's coming on next job crank shaft bearing supports.






Stew


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## SBWHART (Sep 30, 2011)

Well it bin a bit of a frustrating day, made a good start on the bearing stands, then my DRO jammed up the read out was just saying the same numbers switched it off and on fiddled with it went and had a cupa, came back switched it on and it was OK 1/2 hr later same thing, had a fiddle left it alone for at bit switched it on all OK 1/2 hr later same thing.

Decided to leave it until the morning when its cooler, its bin darn hot her in the UK, but you would have thought it could handle a hot UK day, any of you guys experienced similar problems  ???

Stew


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## Brian Rupnow (Sep 30, 2011)

How hot has it been Stew? We are into our early fall "normal" here which is about 20C daytime highs (about 70 degrees F), cooling off to about 40F at night. You are in England, aren't you?


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## Jasonb (Sep 30, 2011)

Brian Rupnow  said:
			
		

> Unfortunately there are no British Imperial size shafting that corresponds to 4mm, so I bumped the 4mm shafting up to 3/16" which is 4.76mm.



Brian, what about 5/32" rod easily available here so I would have though it would be the same for you. Infact I've put an M4 thread onto 5/32" material several times as its often easier to buy shorter lengths of imperial than metric from our model engineering suppliers

Oh and 30deg C in my shed when I got home today, too hot for engineering.

J


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## Brian Rupnow (Sep 30, 2011)

Maybe you are right, Jason, but I just called my metal supplier when I seen your message, and they don't carry it. I might be able to get it on "special order" but its not worth the bother when its so easy to modify a plan.---And isn't that unusually hot for your part of the world?


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## Jasonb (Sep 30, 2011)

I'm surprized by that, we can readily get 5/32" in brass, stainless steel, drill rod, mild steel including square and hex and that from a country that went metric years ago :

Yes its a lot hotter than usual, just watching the weather forcast and its quite likely that tomorrow could be the hottest October 1st since 1985 as it's expected to reach 29deg C. Plants don't know whats happening, they have their fall leaves but are comming into flower. But just give it a coupel of weeks and we will probably have a foot of snow 

J


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## SBWHART (Sep 30, 2011)

Brian Rupnow  said:
			
		

> How hot has it been Stew? We are into our early fall "normal" here which is about 20C daytime highs (about 70 degrees F), cooling off to about 40F at night. You are in England, aren't you?



Hi Brian

Yes I'm in England:-CreweCrewe, Cheshire about 50 miles South East of Manchester, my shop must have bin about 30 this afternoon as well, the tin roof doesn't help it's unseasonably hot normal temp for Oct 10 - 15

I never thanked you properly for your wonderful 3D model of the engine its awesome work.

Even tough I draw in metric I often use imperial sizes as I've got a lot of imperial kit, I made the cylinder 1/2" bore and used a 5/8" reamer on the cross head guide. I tend to change things as I go along, using what kit and material I have at hand, and if I see something I don't like the look of I change that as well. Thats what so great about this game drawings are not contractual like in industry, you're only constrained by the limits of your imagination and you ingenuity.

Thanks again

Stew


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## Brian Rupnow (Sep 30, 2011)

Stew--I do the same exact thing. First I design something. I check clearances, fits, concentricity of mating holes, the models and drawings are flawless. (To me anyways). Then I start to machine it---oh, Damn---I haven't got a reamer/cutter/drill/whatever the right size!! Do I go across town to the toolshops and buy the right sized peice of kit?--Of course not!!! I change the drawing to reflect what I have in my shop right NOW! The drawings I post at the end of one of my projects have sometimes "morphed" into something considerably different than what was initially posted. Thats why I warn people right up front--"Don't save these initial drawings---Wait for the .pdf files at the end of the job."


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## SBWHART (Oct 1, 2011)

Got up this morning bright and early nice and cool in the shed and the DRO worked without a hitch, I think the problem must be temperature related, but the UK is not known for its high temperatures, you would have thought it would work at temperatures greater than 30 C.

The bearing support is a tail of a cleaver idea coming apart.

Squared up A piece of jig plate and fly cut it to the correct thickness.






My idea was to make both out of the same piece, as mirror images, first thing I realized was that my co-ordinates on the drawing were all wrong, I seemed to have snapped onto the wrong point when doing the dimensions and they are a mile out so I had to go back on the computer and correct the drawing.

Drilling the corner holes out went fine.






Spot the deliberate mistake:-the two supports are not identical one has an extension for the cross head guide to fasten to, I went and put a 20mm drill right through it. :'( 

I out cleavered my self with that one.  :

Ok make another one, just a single this time and leave the support untouched.






Her they are waiting to have the rest of the unwanted bits chewed away.






Stew


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## SBWHART (Oct 2, 2011)

Finished of the supports.

I stuck the two supports together with two way tape, and made a couple of plugs to go in the holes to stop things moving around, I also made a filing button, for the top eye.

It was then a matter of nibbling material away from where its wasn't wanted.

In the mill






And with files.






And used a slitting saw to cut through the base, and cleaned across the base with a fly cutter, I'd plugged the bearing hole together, so the crank shaft will sit perfectly level.






A bit more work with files and they are looking something near, I'll tidy them up a bit more but has they are going to be painted they won't need polishing.






Stew


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## Brian Rupnow (Oct 2, 2011)

Looks very good Stew. I made the same stands and ended up with one about.7mm taller than the other!!!    I am going to cheat and loctite a .7mm fill plate to the underside of the short one). I am not posting any progress on mine, just working away in the background. One thing I noticed this morning while building the cam.--On previous cams I have built, the hub was offset to one side with the set screw in the offset part. This let me "play with" the valve timing untill the engine worked at its best. This cam is going to be a beast to adjust as it requires dismantling the eccentric strap to get at the set screw.


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## SBWHART (Oct 2, 2011)

> One thing I noticed this morning while building the cam.--On previous cams I have built, the hub was offset to one side with the set screw in the offset part. This let me "play with" the valve timing until the engine worked at its best. This cam is going to be a beast to adjust as it requires dismantling the eccentric strap to get at the set screw.



Thats very true Brian, they need to be on the other side, When I built the over crank I had problem tapping the cam through the thicker section, the tap didn't reach far enough, so I moved it 180 to come through the thinner section:-as you said, this makes it difficult the set the timing, for some reason I drew the popcorn up with the set screw coming through the thinner section, it could quite easily come through the thicker section as the cam is a lot smaller.

Another problem I had with the over crank cam was that I used M2 grub screws these were just not man enough for the job, the cam kept slipping so I had to tap them out bigger to M3.

Things will be slowing down on this build over the next couple of weeks due to family commitments, which is a bit frustrating as it's getting so close to a test run, but I will be getting the pleasure of seeing my grandchildren.

Stew


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## Brian Rupnow (Oct 2, 2011)

Stew--I meant offset to the outside like this so that the grub screw was always accesable, not covered by the eccentric strap. And yes, grandchildren are great. Wife and I had two of ours over today for lunch and a "visit" The seven year old is really proud of her reading skills, and wants to read to us, the four year old can't read but fakes it-----no way her older sister is going to get all the attention!!!


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## tel (Oct 2, 2011)

I usually put the grub screw in at 180° to that - on the theory that it is a little less visible with the eccentric wall beside it.


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## cfellows (Oct 2, 2011)

I'm liking the way that crosshead slide came out. The whole assembly, including connecting rod, is very nicely done. I like the way the con rod connects to the crosshead. Wouldn't have thought of that on my own... :-[

Chuck


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## SBWHART (Oct 3, 2011)

Thanks Tel, Chuck, Brian

That is certainly a better way of fixing the cam, there is plenty of room on the crank to do it this way with this engine, when room is tight between the crank as in a loco or in my over crank engine, you have to put the screw under the eccentric sheath. I think I will adopt this better method on the popcorn.

Thanks for your input guys.

Stew


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## SBWHART (Oct 3, 2011)

This will be the last post on this job, for over a week going to have a house full of kids and grand kids.

I decided to make the crank shaft with a disc throw, quite a few of the popcorn engines I've seen [ics of have this set up so thought I'd give it a go.

With a chunk of steel in the chuck turn the od and centre drill, then centre it on the mill a off set it by the throw and drill with a number drill just below the size of the crank pin so its a tight fit. One thing they do with this type of crank is maching out a curve oposite the crank pin to balance the crank so using the rotary table mill a 60 deg curve.












Then still in the chuck back to the lathe and drill out for the crank shaft again using a number drill so that its a tight fit.

Then skim it off to correct thickness, the material I'm using is tool steel used to make draw dies from, high carbon with bits and bobs of other things in it, I'm familiar with this steel and know it turn well with high speed tools, but it produces wicked razor sharp snakes of swarf.






Glue the shaft and pin in






Turn up the main bearings and glue them in.






Time for a few hows it looking shots.











Not bad.

Stew


.


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## maverick (Oct 3, 2011)

Stew, The engine is coming along great. Your drawings and build pictures should get me
moving on my own.

  Regards,
  Mike


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## kustomkb (Oct 3, 2011)

Very nice work you are doing Stew.

It is looking great!


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## Brian Rupnow (Oct 3, 2011)

Looks marvelous, Stew!!!


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## danstir (Oct 3, 2011)

Really coming along! You make it look simple.


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## cfellows (Oct 3, 2011)

Very nice work, Stew. It's looking fabulous. I don't mean this as a criticism, just a suggestion and this may not be an option... Do you think the engine might look better with a larger flywheel? 

Chuck


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## SBWHART (Oct 3, 2011)

Thanks Chaps.

Chuck:- I see what you mean the cylinder looks slightly over scale, a bigger fly wheel would componsate for that.











Stew


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## Lesmo (Oct 4, 2011)

I have to agree with Chuck on this one Stew, and also comment that in comparing the disc crank and the usual one, I prefer the latter, although far be it from me to criticize the master. 

Are you exhibiting your overcrank engine at the model engineering exhibition in Warwick on the 14th, I hope you are as I would love to see it.

Cheers Les  :bow:


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## SBWHART (Oct 4, 2011)

Hi Lesmo

No I'm nit at Warwick, but it will be at Sandown in December.

Stew


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## Lesmo (Oct 5, 2011)

Re my previous comment which my better half later read. She said that it was not polite to say that I preferred the other engine to yours, which was not at all what I meant, but I guess it could be taken that way. I was observing that a disc crank does not convey the sense of fluid movement nearly so well as does a conventional crank.

Cheers Stew, see you at Sandown if we are not up to the gills in snow by then. 

Les


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## SBWHART (Oct 5, 2011)

Lesmo  said:
			
		

> Re my previous comment which my better half later read. She said that it was not polite to say that I preferred the other engine to yours, which was not at all what I meant, but I guess it could be taken that way. I was observing that a disc crank does not convey the sense of fluid movement nearly so well as does a conventional crank.
> Cheers Stew, see you at Sandown if we are not up to the gills in snow by then.
> Les



Don't worry about it Les all comment are greatly received.

I'm still thinking about tghat crank myself, easy to change it back.

My boss sometimes sensors my posts, by saying that's a bit ladish/sexist isn't it, or that's spelt wrong, that serves me right for marrying a school teacher:- being bossy comes with the job.

Hope she doesn't see this :big:

Stew


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## SBWHART (Oct 12, 2011)

Well back off holiday, and got another part ticked off:- the eccentric.

Decided to use the design that Brian suggested.

Using a bit of mild steel bar first turn a 5mm wide groove to 20mm dia, and put a small centre drill into the end






Then over onto the mill and centre under the spindle.

Off set the mill to the throw of the eccentric and put in another small centre.

With a independent four jaw in the lathe and using a woble bar get the off set centre running true.






Put a 7.5mm drill through followed by a 8mm reamer.

Back in the selve centring chuck turn a little boss to take the fixing grub screw, and part off






Set up in the mill a drill and tap M3 for the grub screw.






Thats that one done.






Stew


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## bearcar1 (Oct 12, 2011)

Hello Stew, I've been following along and must say it is/has been a delight. That crosshead guide still astounds (scares the crap out of) me. It is interesting to note the visual differences that the engine has with the solid crank disk as opposed to the singular arm. The former gives a bit of flavor similar to the Tangye engines or perhaps a Corliss in a way. Overall, I like the looks either way and am really looking forward to seeing your creation run. Well done and I hope other things are going well for you.

BC1
Jim


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## SBWHART (Oct 16, 2011)

Hi Jim thanks for you comments, I've bin trying to get my-head round modeling a Corliss type valve gear, got lots of pics and videos of them from my visits to engine houses, still can't fathom a way ???.

Made the eccentric sleeve over the past couple of days, every time I make an eccentric sleeve I seem to end up making it a different way than the time before, I think that comes from making them from whatever material I have around at the time.

For this one I had a tub end from a bit of 45mm bar.

Started off in the lathe faced it off, centre drilled it and stuck a 1/2" drill down it.






Then keeping it on the chuck transfered over to the RT centered under the mill spindle, and with a 3mm slot drill cut the shape out.






Whilst I got it centered scribed a line across the middle, this will help set up for drilling a splitting.






Then back over to the lathe things were a bit tight for room but managed to part it off:-still got enough of the stub of bar left for a flywheel sometime.






Then using the scribe marks lined it up level in the mill and drilled and tapped the holes.






Then with a slitting saw cut it in half.






Then set it up in the four jaw, using my centre height gauge get the split on centre, its more important that you get the split centered than getting it exactly in the middle 90 deg from the split.

And bored it out for a good fit on the eccentric.






Her it is assembled.






Stew


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## SBWHART (Oct 17, 2011)

Moving on completed the base.

Measured the centre height to the crank shaft and the piston rods take one from the other and thats what the base needs to be made with mine it came spot on 14mm.






Fly cut a chunk of ally square and to size.

Then marked out uts centre and mark a square to match the base of the cylinder.

Drilled the clamping holes






Then with a 10mm dia ball nosed cutter and the mill head slewed over 20 deg, mill a nice flared foot, working to the lines marked.






This is what it looks like.






As an aside any one know whats going on with the madmodder site bin unable to log on for over 24 hrs now.

Stew


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## SBWHART (Oct 17, 2011)

Another bit done the slide valve coupling.






Not many more to do now.

Stew


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## Captain Jerry (Oct 17, 2011)

Stew - I have been watching with pleasure as this build unfolds. It looks like you are about down to the final assembly. Don't forget to put the drive pulley for the governor on the shaft.  ;D   Looks like there is plenty of room for it.

Jerry


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## SBWHART (Oct 17, 2011)

Thanks Jerry

I'm planning on fitting a Governor and a few other bells and wistles, you see pictures of Popcorn engines that look like they've got a Christmas tree growing out of them: they have bits of pipes sticking out every whare.

I'll concentrate on getting a running engine before I enbark on that part of the build though.

Stew


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## SBWHART (Oct 18, 2011)

The valve rod support, I drew it up fancy and didn't think to much on how to make it, but when it came to it, I realized it was quite an awkward shape, I could have redesigned it, but I kind of liked it as is was. The important part is for the hole to be on the same centre height at the valve rod, so decided it would be easier to make it in two bits and bring it to the correct height by adjusting the base thickness.

With a bit of 10mm brass bar first turned a little 4mm dia chucking piece on the end, then over on the mill drill the hole for the valve stem and mill the flats.







Cut it off to length and centre drill and tap the other end M3, then gripping on the chucking piece, turn the tapered bit.






Sorry pic not very good.

Cut the chucking bit off, and make the base adjusting its thickness to get the correct centre height for the hole.

These are the bits.






I'll whittle that square end sticking up into a round later.

And how its looks.






Just got the base to machine up, but before I'll do that I want to get all the bit loosely fitting together so I can get the positioning correct.

Stew


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## Lesmo (Oct 21, 2011)

This is looking like another winner Stew, nice work.

Les


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## SBWHART (Oct 23, 2011)

Thanks Les

Though it nearly wone the record for the longest distance an engine as ever been thrown.

After three days of trying I've eventually got it running, some of the problems were down to my hamfistedness, I distorted the bore in the cylinder because I was clamping it to the base with over long screws, took me a while to work out why it was getting tighter and tighter, had to run the reamer done the bore to get rid of the tight spots.

The as Brian had pointed out the cylinders were on the short side, I had sussed this out and increase the length by 2 mm, but that was hardly enough, so any of you guys who had the drawings off me make a note to increase the cylinder length by at least 3mm.

The I went and seized the main bearings up twice running it in with a Black and Decker.

You never truly understand an engine until you come to put it together and this was no exception, it doesn't like any tight spots as all.

But it is a runner.

I'll post a video later today.


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## ShedBoy (Oct 23, 2011)

Nice work Stew a real pretty engine. Looking forward to the vid.
Brock


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## steamer (Oct 23, 2011)

Looking great Stew!

I really like the proportions....can't wait to see what the "surprises" are!

 ;D

Dave


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## SBWHART (Oct 23, 2011)

Thanks Dave Brock











And the video

[ame]http://youtu.be/1QaTBWvG5bs[/ame]

Stew


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## ozzie46 (Oct 23, 2011)

Nicely done Stew. Nicely done.

 Ron


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## steamer (Oct 23, 2011)

Great Video Stew....I love the sound of the engine.......and the builder! ;D

Dave


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## Brian Rupnow (Oct 23, 2011)

Stew--Thats a sweet engine, no matter which side of the Atlantic it was built on. You have done a marvelous job there, and I commend you!!! I thought that I was incredibly fortunate when mine started right up with no trouble after a two hour "run-in". By the way, since this is the first engine I have built with "glands" on the piston and valve rods where they exit the cylinder and valve body, what do I use for packing?----Brian


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## SBWHART (Oct 23, 2011)

Thanks Guys

Brian I use graphite yarn just a couple turns around the valve/piston stem. You also have to get the nut bore and the thread as concentric as you can so I make them at the same time. You don't have to over pack the gland I just tighten down on the packing until I feel it starting to hold the rod.

You can also use an O ring or PTFE tape the sort of stuff you use on pipe joint just twist it to form a string, you can use it on pistons as well.

Stew


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## dsquire (Oct 23, 2011)

Stew

Congratulations on having another runner. Nice looking as well. Thanks for taking us along for the ride. :bow:

Cheers 

Don


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## Captain Jerry (Oct 23, 2011)

Stew - Nicely done. A great looking engine as well as an interesting tutorial. I'm sure that there are lots of popcorn engines that will be built because of your inspiration.

I'm not leaving my seat. I know there is more to come.

Jerry


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## jonesie (Oct 23, 2011)

nice job stew,and a nice runner.just in the process of making my curved spoke flywheel.hope mine turns out as good as yours and thanks again for the plans. jonesie


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## steamer (Oct 23, 2011)

Something on this engine just screams to me....old time multi pole generator between the bearing pedistals........anybody thinking what I'm thinking?

Dave


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## SBWHART (Oct 24, 2011)

Thanks for all your kind comments Guys its bin an ejoyable and interesting build, still a bit more to go before its finished.



			
				jonesie  said:
			
		

> nice job stew,and a nice runner.just in the process of making my curved spoke flywheel.hope mine turns out as good as yours and thanks again for the plans. jonesie



Hi Jonesie good to her you're making progress I'd be interested in a few pics if you can.

Stew


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## SBWHART (Oct 27, 2011)

In order to make the body for the governor I need a ball turning attachment, being a bit of a tight wad I didn't want to go out and buy one and I wanted something that would be quick and cheep to build, and I tough of my RT, I hunted around my stash and came up with this lot.






A couple of mornings work and I had got myself a ball turner.






Here's a picture of my balls






 :big: :big: :big: :big: :big: :big: :big: :big: :big: :big:

Their fly balls for the governor I could have bought some 1/2" brass balls but I wanted to give it a try.

Stew


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## gbritnell (Oct 27, 2011)

Hi Stew,
Another very nice engine for your collection. I know how much it takes to scratch build and you did a great job.
gbritnell


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## danstir (Oct 27, 2011)

Great engine! Fun to watch running. Thanks for sharing!


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## Brian Rupnow (Oct 27, 2011)

I think Marv would point out that you have turned "Ogives". I never heard that term before, but on one thread last year somebody was turning egg shaped balls with pointy ends, and thats what Marv said they were.


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## Maryak (Oct 28, 2011)

sbwhart  said:
			
		

> In order to make the body for the governor I need a ball turning attachment, being a bit of a tight wad I didn't want to go out and
> Here's a picture of my balls
> Stew



Do you know where the rest of the monkey is ;D ???

Best Regards
Bob


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## SBWHART (Oct 28, 2011)

Thanks George/Dan/Brian/Bob

Brian



> I think Marv would point out that you have turned "Ogives". I never heard that term before, but on one thread last year somebody was turning egg shaped balls with pointy ends, and thats what Marv said they were.



Good eye site that man, they are 12.3 dia about 1mm undersize from being a true ball, I needed to bring the tool forward a touch to make them a ball at 1/2".

But hey they are close enough to do the job :big:

Bob



> Do you know where the rest of the monkey is



Probably holding up the rest of the balls, 

"Cold enough to freeze the balls off a brass monkey" is an old navy expression, a brass monkey was a square of brass they used to stack the cannon balls on in a pyramid, when it got gold it contracted and the balls fell off, hence the expression.

Thanks for the interest guys,

I've bin busily drawing up the governor and things, I'll post the drawing when I've got it done.

Stew


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## Lesmo (Nov 3, 2011)

Those are an almost perfect set of goolies Stew and I like your lateral thinking in their production. 10/10

Les :big:


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## mklotz (Nov 3, 2011)

sbwhart  said:
			
		

> "Cold enough to freeze the balls off a brass monkey" is an old navy expression, a brass monkey was a square of brass they used to stack the cannon balls on in a pyramid, when it got gold it contracted and the balls fell off, hence the expression.



Balderdash...

http://www.snopes.com/language/stories/brass.asp


----------



## SBWHART (Nov 3, 2011)

Ho well thats another ball story dashed to peices, but I like the story ;D

Stew


----------



## SBWHART (Nov 3, 2011)

Things slowed down on this over the last week what with visiting our son up in Glasgow, and i wasn't too happy how it was running far to sluggish, so I've spent a few days tinkering with it, the engine that is. Slowly chased the stickiness out of it, final part was to make a new front cover, for some reason or other it was nipping the piston rod and slowing things up, so made a new one making sure, everything was correct, that did the trick its running great now.

Also spent a bit of time drawing up the governor







Your probably thinking how the hell is he going to make that, well I've no bloody idea also  ???

 ;D

But you don't know what you can do until you try.

First part the swiveling bit.

Rough out a chunk of brass bar.

Then form the domes, things were a bit tight so I had to finish off the back dome with a file and Mk 1 eye ball.






Looks ok

Tomorrow I'll start to mill it out.

Stew


----------



## bearcar1 (Nov 3, 2011)

Well done Stew, I thought that ball turning tool would come into play here, BRAVO! A bit of silver solder here and there and I can see a governor that would be the envy of the Cretor's Co. ;D

BC1
Jim


----------



## SBWHART (Nov 4, 2011)

Thanks Jim


Good mornings work in the shed, finishing off

Keeping the job in the chuck transfer over to the spin-indexer and fly cut the flats.






Then find the centre of things and zero the DRO.

Drill 






Then off set and drill the 1mm holes fly the fly ball arms.

Turn it through 90 and mill the 2mm slots for the fly ball arms with a slot drill.






For those of you who don't know what a spin-indexer is here's a pic of the set up.






Then still keeping the job in the chuck put it back in the lathe and finish off the diameters so that everything is nice and concentric just in case anything moved under the mill.






OK again keeping it in the chuck back onto the spin-indexer and mill the 3mm dia groove for the drive belt I just turned the indexer by hand to cut the groove.






Back onto the lathe to part off.






The reason I left the big bit sticking out at the front is to give me something to chuck onto to finish the back end.

So holding onto the chucking piece, clock up true.






Drill through for the spindle then open out to 12mm with a boring bar for the bearing.






Then protecting the finished dia, turn it round in the chuck and skim the chucking piece down and dome the end.






Job done, needs a bit of tidying up with a file and the shape is a bit off but it will do the job fine.











Need to buy a new tank of propane for the next bit.

Stew


----------



## Captain Jerry (Nov 4, 2011)

Stew

This is the part that I have been anticipating. A thing of beauty and a joy to behold.

Jerry


----------



## peatoluser (Nov 4, 2011)

Now thats a well thought out machining sequence.
I think we can all learn something from the way you approached the job.
really enjoying the build thread

peter


----------



## Path (Nov 4, 2011)

Stew ...

Thanks for the sharing.

Love the way you transfer from the lathe to the mill and back ... great stuff. :bow: :bow:

Will be watching for other neat things.  

Pat


----------



## SBWHART (Nov 4, 2011)

Thanks for your kind comments Guys




			
				Path  said:
			
		

> Love the way you transfer from the lathe to the mill and back ... great stuff. :bow: :bow:
> 
> Pat



Pat:- Swapping things over like that is a little trick John Bogstandard showed me, its all about having a system of tooling, with the Chinese cheep chuck mounting, its quite easy to make adaptor plates so you can swap the chuck or ER collets for that matter from lathe to spin-indexer- to rotary table and back again, it saves a lot of clocking and if you make the adaptors accuratly you keep consistency spot on.

Johns based his sytem on the Myford Chuck mount.

Stew


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## SBWHART (Nov 5, 2011)

Got on with the fixed part of the governor, this is the bit that has the packing gland in the real job its sit in the little loop so you can replace the packing without having to strip everything down, well thats what I think it does, I'm going to cheat with this as I cant think of a way to get in and tap the hole and at the same time screw it onto the steam chest, so I'll just fiddle it and make it look like the real thing.

Fist job rough it out.






Then with the ball turner form the rads it was a bit awkward get the back rad done because of hitting the chuck, so I had to eye ball some of it.

Looks ok






I scratched my head on how to do the next bit, doing the out rigger for the belt jockey wheel. In the end I just filed a lump of brass to match the radius and screwed it to the body with a 6ba brass screw.






Then silver soldered it.






I left plenty of meat on so it was over to the indexer for milling.






And locating and drilling the holes.






So this is how it came off the mill






Then I turned up a filing button and using this as a guide whittle the unwanted stuff off.






Then back onto the lathe and parted it off the bar.






Then it was a matter of using the chucking pieces to finish off each end.






Time for a hows it looking shot






Not bad

Stew


----------



## maverick (Nov 5, 2011)

Just like icing on the cake. Wonderful job. Looking forward to the rest like a kid waiting for christmas.

 Regards,
 Mike


----------



## JorgensenSteam (Nov 5, 2011)

That is impressive work Stew.
Thanks for posting.

Pat J


----------



## ozzie46 (Nov 5, 2011)

Well done Stew. I learn more every time I look in. Thanks :bow: :bow: :bow:

 Ron


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## Captain Jerry (Nov 5, 2011)

How's it looking? Looks great from here! But I suspect that you are holding something back. Where is the air line?

Here is a suggestion for the gland, if you don't mind.  Instead of the threaded spigot that you have at the bottom, use a nipple that threads up from the bottom, and rises a few threads proud of the oval opening. You can then use an external, cap type gland nut. The lower end of the nipple will then screw down on the top of the chest or whatever you have planned to fit between the chest and the governor.

Jerry


----------



## Path (Nov 6, 2011)

Stew ...

Another winner! 

How did you silver solder on that chunk of brass ... that's impressive. 

Thanks for sharing.


Pat


----------



## SBWHART (Nov 6, 2011)

Thanks for your comments and suggestions Chaps.



> How did you silver solder on that chunk of brass ... that's impressive



Pat

As well as fitting the chunk to the rad, I filed a flat down the screw to allow the solder to wick in, applied some "tenacity flux" before screwing it together.

I just stood it on the hearth like this







The chunk of brass wasn't going anywhere the screw kept it in place.

Then I just heated it up with a propane torch, you have to look out for temperature clues:- the flux goes a powdery white then black and then sort of glassy when you see that your getting close, then I just touched on with the easy flo solder, both sides and watched the solder melt in and stopped feeding it in when I though there was enough, let it cool to black and quenched it in water, I didn't bother with an acid pickle as I was going to machine so much of it away.

After machining you can see a faint 1/16" arc of soldered joint.

Cheers

Stew


----------



## tel (Nov 6, 2011)

Not that it makes any difference to the finished product (which is excellent, btw) but wouldn't it have been easier to mill a slot in the side of the 'ball' to accept the block?


----------



## SBWHART (Nov 6, 2011)

Thanks for your input Tel.

I did contemplate that but as the block would be milled down to 6mm wide the same as the ball it would mean that their would only be a little bit of solder keeping it in place at the ends, which may have been enough, but I went to the Forth Rail Bridge school of over engineering, so went for the extra security.

The rail bridge is standing firm after 100+ years and good for another couple of 100






The road bridge is falling down after 50 years






 :big:

Stew


----------



## Blogwitch (Nov 6, 2011)

Stew,

You forgot to mention that big bits are still falling off the rail bridge due to stress and corrosion, rivets and bolts popping etc, to such an extent, the houses underneath have nets above them to catch it all, but it is still considered safe enough, because of gross over engineering in the first place.


John


----------



## SBWHART (Nov 6, 2011)

Bogstandard  said:
			
		

> Stew,
> 
> You forgot to mention that big bits are still falling off the rail bridge due to stress and corrosion, rivets and bolts popping etc, to such an extent, the houses underneath have nets above them to catch it all, but it is still considered safe enough, because of gross over engineering in the first place.
> 
> ...



Hi John

They've stripping the many, many, tonns of old red led paint off it, people were speculating that it was the paint that was keeping it together, :big: its now got a new paint job, that they recon will last for 50 years, for the first time in it's life its not beging painted.

For me it just looks the job.

As an aside my sons father inlaw is a cival engineer and as a young student he walked over the road bridge on the suspension wires, rather him than me.

Stew


----------



## Brian Rupnow (Nov 6, 2011)

Stew---You are doing lovely work there. When I pulled my Popcorn engine apart to install some teflon packing in the glands, I found that when I went to reassemble it there was a bind. I ended up installing a washer about .035" thick between the crosshead guide and the bearing support column. This seemed to free things up considerably. The 3D cad model tells me the washer/spacer is not required, so I can only assume it reflects more on my machining accuracy than on the plans.


----------



## SBWHART (Nov 6, 2011)

Thanks Brian

They don't seem to like any tight spots, in fact I'm a little woried that it won't have enough humph to drive the governor, and I've got a hankering to add a clown turning a crank. The only thing to do is try it and see what happens, if nothing else it will look the part. :big:

I didn't get anything done today.

But thought I would ask a ? of you guys, I may have asked it before but no harm in asking again.

I've been trying to get my head round the plumbing you see on popcorn engines, no two seem the same, some look like Russian spy trawlers they've got things sticking out every ware.

I'm going to keep it simple along the lines of this.







but without the twirly whirly bit which i've worked out is for a pressure gauge.

But the lubricators the sticky up thing in front of the steam chest looks all wrong to me, its bottom looks to feed into the the steam pipe, but for a displacement lubricator this is wrong.

Has any one got any knowledge of this or access to an engine with a lubricator on they can check out.

Even though I will be running my engine on air and displacement lubricators don't run on air I like the idea of fitting one.

Cheers

Stew


----------



## steamer (Nov 7, 2011)

Hi Stew,

It's been years since I saw the one I worked on....those grey cells are history.

I would bet that once the engine is divorced from it's cart...the plumbing went with the whim of the engine owner....So I wouldn't get to hung up on it....unless you can find a picture of an original, do what makes sense.

Dave


----------



## SBWHART (Nov 7, 2011)

steamer  said:
			
		

> Hi Stew,
> 
> It's been years since I saw the one I worked on....those grey cells are history.
> 
> ...



Thats good advice Dave, 

Its bin suggested on another site that they had a tube coming up the inside to the oil level.

As I will only run with air I'll just make a plain lubricator with an air tight lid, so when i want to oil the cylinder i'll just undo the lid and put a few drops of oil in.

Thanks

Stew


----------



## steamer (Nov 7, 2011)

That lubricator looks like a graphite pot, but it would seem unclear as to how that valve is constructed. If the pot is placed after the throttle/stop valve, that would make sense as you close the throttle, open the top of the graphite pot, add some, close the cover and when you open the throttle/stop valve it would rush into the engine....the vast majority of which would blow out the exhaust and onto the ground...but at least it wasn't on the popcorn! :big:

I don't think these engines worked real hard but were a novelty.....so that method would work.....steam engines don't hold grudges and put up with all kinds of insults and keep going.

Dave


----------



## bearcar1 (Nov 7, 2011)

Hi Stew, you are having the same problem I was having when I built the oscy version of the Cretors as a gift to my Dad. I fin ally wound up very loosely following the plumbing layout of an engine that was on display at the Museum of Science and Industry and moved on. It was not "original" to scale by any means but it served it's purpose and I have yet to have anyone comment on the fact. Here is a drawing of a lubricator I found in an old Model Engineering magazine and it reminds me of the lubricator you are pondering. Maybe this will shed a bit of light on an internal scheme. 

BC1
Jim 

View attachment upright lubricator.pdf


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## SBWHART (Nov 7, 2011)

Hi Jim

That drawing is just the ticket, much apreciated.

Thanks

Stew


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## steamer (Nov 7, 2011)

YUP pretty basic displacement lubricator....

Dave


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## SBWHART (Nov 7, 2011)

Ok that one ? answered, now for another


Is their anything worse than a good dose of man flue?:- it,s hit me with a vengeance, so I've cozied up all day in front of the computer, drawing up the supply manifold.






Stew


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## SBWHART (Nov 10, 2011)

Dragged myself into the shop today and finished off the bits and bobs for the governor:-

Turned up the jocky wheels and crank shaft pully. No pics

Then made the fly ball arms, I used mild steel

Squared up a block and first drilled the pivot hole 1mm and the corner holes.






Then with a milling cutter milled one side deep enough to make the two arms, then swiveled the vice round, and milled the angled bit.






Then split them off with a slitting saw.






Spent a little time filing them to fit, and filed the end into a rough round then run a M2 die down it.

Drilled and tapped the balls 






I took delivery of some 3mm dia o ring cord this morning that I'm going to use for the drive belt, so time for another hows it going to look shot.






Stew


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## SBWHART (Nov 11, 2011)

Thanks:- Dave/Saw/Bernd

Ok with my bigger watermark now in place.

Made the manifold.

Started with a bit of brass bar, turn it down to size and part off.






Then drill and tap one end marked the tap up so i wouldn't go in too deep.






Turned it round and did the same to the other end and also thread the OD 3/8*32 ME.

Then mark out where the holes are to go, then in the spin-indexer drill the holes 3mm for the couplings, also milled a small flat on the hole position so the coupling would have something to sit square against for soldering.






Turned up the coupling with a little 3mm nipple on the end 3mm for a tight fit in the manifold.






Couplings pressed in.






Onto the silver soldering just added a little bit of flux, and a few nuggets of solder and heated them up to everything melted in, then into the pickle for 1/2 hr.

Back onto the spinindexer, square up onto one of the coupling pick the hole centres up and drill.











Wilst it was in the pickle made the stop valve nut.

Her it all is






Stew


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## Brian Rupnow (Nov 11, 2011)

Stew---As usual, nice work!! Why the watermark?---Brian


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## Blogwitch (Nov 11, 2011)

Stew,

If I could suggest something with reference to your watermark.

Leave it the same size but relocate it into the centre and reduce the opacity to something between 5 & 10%.

It will fade into the background and not interrupt the viewing of the picture but it will still be well watermarked. As it is, it could distract from the actual picture or cover something up of interest.

John


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## SBWHART (Nov 12, 2011)

Brian

I've increased the size of the watermark because of this 

http://www.homemodelenginemachinist.com/index.php?topic=16479.15

and this Looks like you are not the only one, this looks like Stew Harts engine
http://tech-domain.com/viewthread.php?tid=40065&extra=&page=1

if you have a look at the site you will find some of your work.

Thanks for the tip John I'll have a try at that, sounds a good idea.

Stew


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## SBWHART (Nov 13, 2011)

Finished off most of the fittings for the manifold.

To make the body for the whistle valve just square up a chunk of brass and put a small centre where the coupling will be turned.






Then using the good old wobble bar get it on centre in the four jaw chuck

Turn and thread 1/4*40 and drill through 2mm and part off

Over onto the mill and mill a 3/16 slot across it.






Drill a 1mm hole for the lever pin






The lever is made from some 3/16 square mild steel bar, so in the self centering four jaw with the compound slewed over a couple of degrees turn up a nice shaped handle, and part off.






Drill a 1mm hole for the pivot pin.

Next bit the valve spindle, from a bit of 8mm dia stainless, centre drill and with a running centre turn and thread.






Flip it round and turn and thread the other end again using a running centre, to turn the cone I used a small fixed steady that I made some time ago it just clamps on the running centre.






These are the bits 






and assembled






Cheers

Stew


----------



## Captain Jerry (Nov 13, 2011)

Stew

Thank for showing this in detail. Engineering is so much more than engines and this is an excellent example of attention to detail. I need to learn a lot more about piping and valves.

Jerry


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## jonesie (Nov 13, 2011)

stew it is really looking good looks like i need to get busy to get mine done. nice work and detail. jonesie


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## steamer (Nov 13, 2011)

Love the steady rest....it is so much better for small parts than the conventional ones!

Dave


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## bearcar1 (Nov 13, 2011)

Truly spectacular attention to the finer details Stew. My jaw just drops when I see some of your ideas and work in progress. It's always such a treat to see. That steady follower is going into my brain trust (that is if I can still get the rusty door open :big

BC1
Jim


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## SBWHART (Nov 14, 2011)

Thanks for all your kind comments guys. that little steady I saw some ware and though that's a good idea, so when the need arose I made one, and glad I did.

Next bit up is the union coupling of the manifold to the steam chest, this had to be a naval type coupling otherwise the darn thing wouldn't screw together. The bits were just straight forward machining.

Her they are the little round mushroom bit screws into the square body through the nut its fixed in place with stud lock, tightening the nut onto the union on the manifold tightens onto it an make the seal, hope that made sense  :







Also made the oiler as I won't be running on steam its not a proper displacement oiler just a look a like, to use just unscrew the cap put a few drops of oil in screw the cap on tight, turn the air on and it will flush the oil into the cylinders.

Her's a pic of it all assembled onto the engine.






Starting to look a bit tasty.

Waiting for some 12mm dia thin wall brass tube to be delivered for the wistle, that will be the next bit.

Stew


----------



## SBWHART (Nov 16, 2011)

Thanks for your interest and support chaps.

Got a little done yesterday, I'm rapidly getting to the point with the build when its all about bling.

Made the stop valve handle out of a bit of broom handle, I just hope the boss doesn't notice.

Turned it up in the lathe and recessed it to take dime, I'll glue it in at final assembly.

This us what it look like.






Stew


----------



## steamer (Nov 16, 2011)

That's awesome Stew.  Best use of a dime I've seen in some time.

Dave


----------



## metalmad (Nov 16, 2011)

nice one Stew :bow:
Pete


----------



## kustomkb (Nov 16, 2011)

That's looking really nice Stew. Great attention to the details.


----------



## SBWHART (Nov 16, 2011)

Thanks for your comments guys.

On the home streach


Our daughter brought the dime back from her resent visit to the west coast, I asked her to bring back some us change just for this just job, taking a closer look at it I realized that each state has a different design on the tail side of the coin, some of them a very nice indeed.

Well I've more or less done all the machining work now, its just down to assembling the pulley for the governor and giving it a trial, then it down to some serious bling work.

Last job making the whistle, not much to show in terms of machine set ups most of it was basic stuff and file work, I followed LBSC instruction for making a loco whistle he was very insistent about getting the shape of the throat correct and the disc slot, it came out fine I get a nice sharp note, that set the dogs howling in the area, I was a bit concerned that it would come with a D flatulent note

 :big: :big: :big: :big:











Her's a few pics of the whistle fitted, I won't post any more pics of the engine now until its all blinged up.

Stew


----------



## danstir (Nov 17, 2011)

It looks great! I love the whistle.


----------



## Lesmo (Nov 20, 2011)

That looks the biz even without the bling, you certainly turn out some very inspiring work Stew. Will you be taking this one to Sandown next month, it certainly would be nice to see it in the flesh, alongside your lovely over-crank engine. I have ambitions to have a go at the latter when I complete my present project, which has been somewhat delayed by various things, like summer, mods to the mill capability and the installation of a new lathe from Warco, following one of those impulse buys at the Warwick exhibition. Must remember to leave the plastic at home when I visit Sandown.


----------



## SBWHART (Nov 20, 2011)

Thansk Guys



> Will you be taking this one to Sandown next month,



Depends if I can get it finished in time Les:- I've a few domestics building up.

I hope to submit an article to ME next year.

I've had it running with the governor, and its now stripped down getting the bling treatment.

Stew


----------



## tel (Nov 20, 2011)

You've done an inspiring job of it Stew - ME should welcome a comprehensive article with open arms! Heck! I'll even go back to buying it when it comes out!


----------



## steamer (Nov 21, 2011)

Looks Awesome Stew!  I really like it!

Dave


----------



## jonesie (Nov 21, 2011)

stew it is looking real good, i like the new parts the gov. and whistle. i have all the large and tough parts done now working on all the little parts. i will post a pic. when i get some more done. waiting to see it run with all the bling. jonesie


----------



## cfellows (Nov 21, 2011)

Really nice looking engine, Stew. Typical of all your great work!

Chuck


----------



## SBWHART (Nov 24, 2011)

Thanks for your interst and positive comments Guys

Things bin a bit slow this week, but I did manage to get the bits that are to be painted painted.


I used a acid etch primer for the non ferouse bits and an ordinary car primer for the ferous bit, I'm using a red metalic paint.






Also made a hard wood base her are the bits






And made a start on engine turning the ally base I'm using some cretex points that John gave me he olso explained the best way to do it :thumbup:

This is as far as i got i was getting a bit boseyed, and didn't want to mess it up and have to start again so I'll come back to it tomorrow and finish off.






Stew


----------



## Path (Nov 28, 2011)

Looking great Stew ... can't wait to see the paint job. 


Pat


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## SBWHART (Nov 30, 2011)

Well as you may have seen elsewhere this engine is now complete so just to finish off this thread hers the completed engine

















And the video

[ame]http://youtu.be/YeJjQCjNys4[/ame]


I've just spent the last couple of days checking over the drawings and completing the drawing for the Governor bits

I've emailed the final drawing to every one who had the early drawings, if I've missed any one my apologies just give me oke: via a PM.

And if anyone else wants a copy just send me a PM.

Stew


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## tel (Nov 30, 2011)

A credit to you Stew - it really captures the spirit of the original!
 th_wav


----------



## steamer (Nov 30, 2011)

Awesome Build Stew!

Dave


----------



## JorgensenSteam (Nov 30, 2011)

Any way you slice it, that is a great looking engine.


----------



## Ramon (Dec 1, 2011)

Hi Stew, you already know what I think from ME forum but it's certainly worth repeating here. 
Extremely well made, very nicely painted _and_ beautifully presented.

Well done - it's a credit to you. Thm: Thm: Thm: 

Regards - Ramon


----------



## metalmad (Dec 1, 2011)

Its gorgeous, Stew :bow:


----------



## danstir (Dec 1, 2011)

I thought it looked great before, but with the new paint lob it is fabulous!!


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## SBWHART (Dec 1, 2011)

Thanks for all your support and kind comments Guys

What next well

I've got my eye on one of these beasts.

http://www.aqpl43.dsl.pipex.com/MUSEUM/POWER/rotaryengines/rotaryeng3.htm

Simpson and Shipton Reciprocating steam engine, best way I describe it is that its works with a captive eccentric.

Antony Mount made one a few years ago and polly model suply castings for it.

From my research only two were made the first was displayed at the great exhibition and drove some textile machinery, this was the basis of Antony Mounts engine apparently a second was made with a diferent power take off but there are no images of it. 

So i think I may use the speculation of this second engine as a basis for my model, got some ideas on how to configure the drive, I don't have any drawings to work to so I'll have to figure things out as i go along, and it will be fabricated from bar stock some how.  ???

Stew


----------



## Captain Jerry (Dec 2, 2011)

Would someone please check on Stew. I think he's gone round the bend.

Jerry


----------



## SBWHART (Dec 2, 2011)

;D ;D ;D ;D

Nice one Jerry

Not quite round the bend.

   

This was posted on madmodder regarding the Simpson and Shipton



> Achim Meyer did one Simpson from bar stock:
> 
> http://dampfforum.info/viewtopic.php?f=1&t=7997&hilit=Simpson
> Unfortunately, you have to become a member of the Dampfforum to see the topic.
> ...



Thats one very nice model:- if you click on the link to the site there is a video of the engine running.


Stew

No its her

[youtube]http://www.youtube.com/watch?v=r76WwOd7RMM&feature=player_embedded[/youtube]


----------



## Lesmo (Dec 3, 2011)

You certainly like a challenge don't you Stew, but having looked at the video I can certainly see the attraction. That lovely fluid motion reminds me of your over-crank engine. This is one I shall certainly not be missing. More power to your elbow young man, we all know you can do it. 

Les


----------



## steamer (Dec 3, 2011)

I couldn't get the links to work

I found it ...here it is
[youtube=425,350][/youtube]http://www.youtube.com/watch?v=r76WwOd7RMM

Cool engine!


----------



## steamer (Dec 3, 2011)

Thats a cool engine and a awesome model.  I'm wondering how tough it must of been to keep to keep the full sized "piston/cylinder"....if we can call it that...lubricated during operation!

Some excellent minds back then...probably to get around the Watts patent..?

Dave


----------



## SBWHART (Dec 3, 2011)

steamer  said:
			
		

> Thats a cool engine and a awesome model. I'm wondering how tough it must of been to keep to keep the full sized "piston/cylinder"....if we can call it that...lubricated during operation!
> 
> Some excellent minds back then...probably to get around the Watts patent..?
> 
> Dave



Dave I think your correct about it getting round the Watt patent, a lot of those weird and wonderfull engines came from that desire.

I've no idea about the lubrication, but one thing that was intersting about the full size engine was that the side plate could be adjusted inward to take up wear.

Antony Mount in his model machined a groove arround the flat rim of the piston and used graphite packing to make the seal.

It certainly calls for a close fit between piston and cylinder.

Thansk for your interest.

Stew


----------



## Dave (Jan 7, 2014)

I like the looks of this popcorn engine , could you send me a copy of the plans.     David Oulton ,  [email protected]  thanks


----------



## gus (Jan 11, 2014)

Hi Stew,
*PopCorn Steam Engine.*
Very well done. Please advise material of belt drive for the governor. I used thick rubber band but they have very short live. The engine frame was very well done.I had to cheat a wee bitty because of the very small mini miil.

Looks like you have stirred up the hornets' nest and now many of us want to build this engine.


----------



## Brian Rupnow (Jan 12, 2014)

Gus--Use a rubber o-ring. They make great drive belts for any kind of model engine, both steam or i.c.--Brian


----------



## gus (Jan 14, 2014)

Hi Gentlemen,
Guess I am the first in the que after Stew to build this Popcorn Steam Engine.
Done three years ago but not completed or painted a I have yet to out in a belt drive for the governor that will last.Bought the Mamod spring belts which was hard to join up.


----------



## robcas631 (Jan 14, 2014)

Outstanding work!


----------



## gus (Jan 15, 2014)

robcas631 said:


> Outstanding work!



Hi Rob,

Thanks but Gus is not trying to hijack Stew's show. Just complimenting and trying to encourage more members to build this engine.

When I saw same engine in the Model Engineer Mag, I got so thrilled and conned myself  into building engine which looked easy to build but wasn't so. Glad I got to finish it as a running engine but not yet a showpiece. Now gathering cobwebs and the wifey boss is not happy.

Got myself conned again into building another 120mm R.Table. The last DIY RT cannot take heavier cuts w/o vibrating.Will post shortly and called the post---------Just another R.T.


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## Brian Rupnow (Jan 19, 2014)

Gus--This is not a popcorn engine, but rather a twin cylinder steam engine of my own design, with a governor of my own design. You can see the rubber o-ring which drives the governor. I use 0.100" diameter O-rings for  drive belts on al of my small (model) machinery. They are available in any length, they don't stretch, and they are very inexpensive.----Brian


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## gus (Jan 19, 2014)

Hi Brian,
Thanks for info.


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## SBWHART (Jan 20, 2014)

Hi Gus

Thanks for you interest in the popcorn engine.

To answer your? regarding driving the governor I used O ring cord that I got off ebay you can join it up to make any length of belt you want using supper glue you just have to make sure you cut the ends square and clean.

Stew


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## gus (Jan 21, 2014)

SBWHART said:


> Hi Gus
> 
> Thanks for you interest in the popcorn engine.
> 
> ...



Thanks.You have solved my governor drive belt problem. Will finish up my popcorn engine plus mounting it on a good looking timber base.


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