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dgjessing

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Feb 16, 2010
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eng4.JPG


I've been screwing around with this for the past month or so, ~half an hour at a time. It's another rotary valve job like my first, except a lot tighter, and perhaps even good looking(?). 3/4" bore, 3/4" stroke.

The cylinder is steel with a brass head soldered on. It's actually got a pretty good bore, honed with progressively finer emery cloth. The aluminum piston will stay up in there as long as my finger covers the port, and fall out when the port is uncovered.

The valve body/main bearing is steel with a brass liner sweat-soldered in place. The shaft is steel. I got a pretty good fit - it doesn't leak much at all.

The flywheel is a fairly massive hunk of aluminum 1/2" thick x 3" dia. It will be pressed onto the shaft.

Metal parts yet to be made include the connecting rod, big end bearing, and the copper air line up to the cylinder. Heresy perhaps, but the frame is going to be wood :)
 
Are you certain that you want to press the flywheel onto the shaft?

That will make it very difficult to adjust the timing. I would consider attaching the flywheel with a setscrew. A 1.5" hole is too long to thread for a small setscrew. Drill a hole through to the bore, thread the first 0.5" or so of the hole for the setscrew and then use a thin brass pusher rod to transmit the force of the setscrew to the shaft.
 
I was just thinking the same thing Marv, if the flywheel were permanently affixed to the crank, timing would be a real beast if not impossible to adjust. The method you describe is the exact remedy for the situation. Also, DG', you may wish to reconsider using wood for the pedestal, wood will warp and change shape and dimension over time and depending on prevailing moisture and temperature conditions, this obviously would effect the line up of the reciprocating assemblies. Use a piece of plate steel and silver solder the cylinder to that instead. Cool looking engine it will be when you are finished.

BC1
Jim
 
I considered the timing issue, but then there is really only one correct way for it to be set - valves closed at TDC & BDC. If it needed to produce peak power that would be another thing, but heck, all it's gotta do is spin around :)

And spin it does: http://www.wsukes.com/temp/eng4.wmv
 
And more or less finished:

eng4-1.jpg

eng4-2.jpg

eng4-3.jpg


I've been running it in yesterday & this morning, probably got around four hours on it so far. I wanted it to be able to run really slow, and it does - 120 RPM! (That's slow enough that you can actually count the turns while watching the second hand on the clock :) ). I'm guessing about 2 or 3 PSI (gauge reads zero...).

As for the frame being wood - yeah, yeah, I know, It's gonna warp all over the place and attract termites! What can I say? Wood work is a whole lot cheaper and easier for me :)
 
Ooohyeah. I have to admit it, that is one slick looking engine. And it sounds like it is a good runner. It's reminiscent of some of the very old steam toys of yesteryear. Well done DG, well done. What method of attachment did you use to hold the cylinder to the frame?

BC1
Jim
 
Thanks ;D

The cylinder is epoxied on. Time will tell how well that works.
 
Running:

[ame]http://www.youtube.com/watch?v=ceF2UQ8Fnro[/ame]
 
Oh, this engine has a load of something... it's on the tip of my tongue..
Charm

Very attractive. Great runner. Such a nice meld of wood, metal, and old-fashion-ness.
Thanks for sharing and showing.

Dean
 
Beautiful engine dgjessing. :bow:

Rick
 
Very nice. I like the way it looks and the way it runs. Great job. Thm:
 
Good job.

I like the combination of wood and metal.

Very clean looking, smooth running and sounds great.

SAM

 
I also like the combination of wood and metal, you have done a beautiful job. :bow:

Ian(seagar)
Coffs Harbour,
Australia.
 
Always a problem coming late...nothing I can add.
Congratulations. I like the looks, the sound, and the speed.
Very nice.
 
I like it, especially the combination of wood and metal. :bow: :bow:

Best Regards
Bob
 

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