Author Topic: Elmer's #42 Oscillating Cylinder Engine  (Read 291 times)

Offline cwelkie

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Elmer's #42 Oscillating Cylinder Engine
« on: April 28, 2022, 11:23:16 PM »
For some reason this little design has held a fascination for me ever since I first saw the drawings.  After completion of the last "larger" project I thought it time to finally get this one done.  It was a good way to use at least some of the tiny bits in the Brass Box.

https://youtube.com/shorts/1WSir95bfBQ?feature=share

Offline EricB

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Re: Elmer's #42 Oscillating Cylinder Engine
« Reply #1 on: April 29, 2022, 02:07:03 AM »
Nice little engines. I built one last year: https://www.modelenginemaker.com/index.php/topic,10234.0.html

How did you create the "U" shaped frame?

Eric

Online Kim

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Re: Elmer's #42 Oscillating Cylinder Engine
« Reply #2 on: April 29, 2022, 05:00:03 AM »
Great little runner there, cwelkie!  :ThumbsUp: :popcorn:

Kim

Offline cwelkie

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Re: Elmer's #42 Oscillating Cylinder Engine
« Reply #3 on: April 29, 2022, 02:13:31 PM »
Thanks guys. I find Elmer's engines fun to do while considering "What's next" questions.

 Eric - I started with a 1" wide, over length piece of 1/4" aluminium flat bar.  Simply used a length of 1" diameter rod as a form/mandrel, my vise and dead blow hammer to bend the arc.  As the sides got closer together, I clamped the rod into the "pocket" being formed to ensure the circular shape was maintained. As the sides approached the intended distance apart, I used a couple of blocks machined to the inside dimension to gauge and control the bend.

Once the plan view shape looked good, I put the part in the milling machine vise with the above blocks  used as spacers and the part "level".  Then the top and bottom surfaces could be surfaced back to be flat and to the target height all around.  (I didn't have any 5/8" material suitable for the base so used 1/2" for the base and made the U-shaped piece 7/8" tall.)

The bearing block locations were machined and drilled after the U-shaped piece and outboard bearing support were bolted to the base.  The assembly could be clamped in the vise and this ensured a consistent height and alignment at all 4 bearings.

Charlie

Offline Dreeves

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Re: Elmer's #42 Oscillating Cylinder Engine
« Reply #4 on: April 29, 2022, 03:47:21 PM »
Great looking engine. I finished mine about a year ago. I made my base as a solid using my cnc. I was not keen on bending the u shape.

Dave

Offline propforward

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Re: Elmer's #42 Oscillating Cylinder Engine
« Reply #5 on: April 29, 2022, 03:57:08 PM »
That's a very fun engine.  :ThumbsUp: :ThumbsUp: :ThumbsUp: :ThumbsUp:
Stuart

Forging ahead regardless.