A Celebratory Engine -Elmer's #8

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arnoldb

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A year ago this same weekend, I pulled my finger from you-know-where, and built my first running engine

I thought a celebration was in order, following the same rules: Build an engine from start to finish in one weekend. I was wondering whether to build a wobbler of my own design or one of Elmer's ones and mentioned this to Rob Wilson. He promptly suggested Elmer's #8 - Scotty. This turned out a good suggestion (Thanks Mate ;D), as this would also be my #8 engine, and would give a good workout to the new skills I learned in the past year, as well as make use of my significantly improved tooling arsenal.

So I started, and finished the #8 ;D. It took a bit of planning; some parts had to be made before others to allow loctite to cure overnight and so on, but I worked out a sensible approach, and collected materials. This is not a full build log like I usually do; most photos are of finished components, but I did add one that I thought worthy as a tip.

Finished engine photos and video is at the end of the post.

Friday afternoon after work started with this bunch o' bits:
normal_IMG_1498.JPG


One of the bits of 6mm ali plate was machined into the engine frame:
normal_IMG_1499.JPG


Another bit of ali became the base:
normal_IMG_1500.JPG


Then I turned the bearing, cross drilled it for the air supply passage and silver brazed a bit of 5mm brass pipe to it:
normal_IMG_1501.JPG


Stopped work for the evening with the bearing pressed into the frame with a bit of high strength retaining compound to cure overnight:
normal_IMG_1502.JPG


Saturday I started by cross drilling the steam passage through the frame and bearing, and made a plug from ali to close up the open end on the frame:
normal_IMG_1503.JPG


A while later, the cylinder block followed:
normal_IMG_1504.JPG


Next the piston and rod; as the rod I had available was 3mm music wire, I didn't bother to thread it for screwing into the piston like Elmer is wont to do; I just drilled the piston center on size for the rod, cleaned everything thoroughly, and silver brazed the rod to the piston; much quicker!:
normal_IMG_1505.JPG


The rod guide followed next; this is the only part I made a booboo on and had to re-do it:
normal_IMG_1506.JPG


The crank disk followed:
normal_IMG_1507.JPG


Next I started on the main shaft; it had to be drilled for a length, and two flats machined on it 180 degrees apart to make the valve for intake and exhaust. To make sure the two flats were 180 degrees apart, I clamped a bit of rod to the first flat after I machined it, and turned in the vise; it was then easy to check by measuring down to the mill table that both ends of the clamped rod was equidistant from the table:
normal_IMG_1508.JPG


The finished shaft; poor picture, as it does not show the longer flat at the back...:
normal_IMG_1509.JPG


While the going was good, I milled and then turned the yoke from a bit of HRS and stopped for Saturday:
normal_IMG_1511.JPG


This morning I made the flywheel after I re-made the faulty rod guide:
normal_IMG_1513.JPG


The slide block was made from a bit of phosphor bronze; I didn't bother to lay it out; just used direct readings from the mill and a couple of calculations - it came out spot-on ;D:
normal_IMG_1514.JPG


Then I assembled everything, and had a bear of a time to get the engine to run. I traced some binding to the yoke which was just a tad tight on the crank disk; some sanding on emery relieved this. The piston was also a bit tight in the cylinder - it fit perfectly yesterday, but the cylinder block was a lot colder today, and had shrunk enough to cause a bit of binding, so I took some more metal off the piston with some fine emery. Then I added copious amoints of oil everywhere, and turned the engine over for a while with the main shaft gripped in an electric hand drill. After a while, things loosened up nicely, and the engine started on air - though it required about 20 psi. After another 20 minutes of running, it was down to less than 5 psi to keep ticking over.

If anybody want to build this engine, I'd suggest a steel / cast iron / brass flywheel; the aluminium one appears a bit light. I think I'll make a steel flywheel at a future date for the engine, as it is very near to being breath powered - it just needs a bit more momentum.

Photos of the completed engine:
normal_IMG_1515.JPG

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normal_IMG_1518.JPG

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And the video; this engine is not counter balanced, so it needs something solid to hold it down; I used a small drill press vise:
[ame]http://www.youtube.com/watch?v=C8YMhDmRwVo[/ame]

This was a nice personal challenge ;D - next up I'll make a boring head, and then I'll notch things up with either an IC engine or a flame gulper.

Many Many thanks to all the good members here on HMEM who have contributed your knowledge and experience - directly and indirectly !

Thanks for checking in !

Regards, Arnold
 
Arnold,

Nice engine.

You finished in one weekend :eek:

Did you stop to eat?

SAM
 
Arnold

Very nicely done!!!

You were ambitious to try an engine in a weekend but you pulled it off nicely. :bow:

Eric
 
Arnold

Congratulations. You have came a long way in the first year. I am looking forward to watching your progress in year 2 as well as the new projects that you will attempt. :bow: :bow:

Cheers :)

Don

 
Great looking engine, also great running engine. I'm really surprised that this only took 1 week-end, this is a great build time.Larry1
 
Congratulations, Arnold!

Wow! Only one weekend! And what a great looker and runner too :bow:


 
Arnold...congratulations!!

Makes me want to know more about where that finger was...but I won't ask. I'll experiment and hope.

One weekend. I have to admit to being jealous. Real jealous. ;D
 
Well i just new you could do it :rant: :rant: :rant: :rant: ::) ;D Rof} Rof} Rof}

Nice one mate :bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow:


Regards Rob

Top job Thm:
 
Man that engines runs smooth as a baby's back side. What a beauty. I am insanely jealous, a little over twenty four hours from start to finish, what did you do Arnold, pee in a can in the corner? Well done, BRAVO!

BC1
Jim
 
Way to go Arnold! It's nice to have another build thread on one of Elmer's engines. After some time, maybe we'll have all them.

How'd you get the parts to come out straight using that curved ruler? :big:

-Trout
 
Nice one Arnold!!! ...And quick too! Remindes me I've got plans around somewhere for a double scotch yolk, may have to dig those out.

Cheers

Jeff
 
Great weekend build Arnold. That Scotch yoke connection to the crank is neat. It looks like it runs real sweet also.
George
 
Very Nice smooth runner.
Sounds great...

Keep up the good work.
 
Thanks Sam - I always make time for a good cooked dinner and quality time for attention to my pets ;)

Eric, thank you; maybe a bit ambitious, but that's where the challenge lay; I machined this engine "in my head" numerous times to make sure it was both possible and safe to try. I'm sure it can be done in one day, but I like my extremities, so I took breaks when I felt tired.

Thanks very much Don. I surprised myself with how far I've come, but I still have a lot to learn... I have a list of projects that just keep increasing in length!

Larry, Thanks !

Thank you Kevin - I'm going to try a heavier flywheel later in the week; maybe I'll be able to post a clip of it running on breath power - that will have me REALLY happy :)

Thanks Ron !

Thank you Carl. Why, the finger was in my ear... :big: Don't be jealous - your life's a bit more complicated than mine ;)

Rob, Thanks Mate ;D - :big: You better get to it; I'm trying to catch up ;D - now, if I can just lay my grubby fingers on refractory and casting sand... :big:

Thank you Jim ! - :big: I have a bit of garden close to the workshop door ;D - but fortunately the house and amenities are not too far away ;D

Thanks Trout ! - I don't think its a "maybe" - I'm just grabbing what I can! - Metalbutcher is on vacation, but he sure gives them a go, and you and others are following closely ;D :big: If my parts looks as bent as the ruler, I know they are good to go :big:

Bob, thanks!

Jeff, thanks. I know I've seen some plans for a double scotch somewhere; I can't recall if those was for an Elmer or someone else's though. Should be an interesting build though ;)

Thank you very much George!

Thanks hobby - it kicks up quite a racket if its not on soft padding as it is very unbalanced. I have yet to hear what it sounds like when mounted on a wooden base; I think it will need rubber feet ;)

Diy89 - thanks, and its a pleasure.

Regards, Arnold
 
Thats a little beauty Arnold. Despite it being a weekend project, each part looks so well finished. Excellent job.

Bill
 
Arnold, that is a sweet little engine. What rpm do you think it gets to while your at full speed. Sounds great also.
Mel
 
Wow Arnold ... you sure don't waste time! :big: :big: :big: It's so unfair that you have so much time to play! I'm lucky if the misses and the kids allow me 2 hours on a Saturday! ;D
Great engine! Thm:

Regards
Wagner
 

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