Author Topic: Doppelmotor - Double Acting Stirling Engine  (Read 3736 times)

toolznthings

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #15 on: April 18, 2020, 01:32:37 AM »
Great work and progress  :ThumbsUp:

Offline yogi

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #16 on: April 18, 2020, 09:47:08 PM »
As promised, today's part is the cylinder sleeve.
The sleeve is turned from 416 stainless (thanks Brian).  ;) Turning the outside and inside diameters to full length and parting off.




Finishing to length.




Milling the notches for the air passages.




The finished sleeve.




The sleeve installed in the cylinder.




Thank you for following along, and stay tuned for more.
Yogi


Offline Craig DeShong

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #17 on: April 18, 2020, 11:24:37 PM »
Lov’in this build.  Your building an interesting hot air engine.

If I might ask, why are you using paper when holding a work piece in your mull vice?
Craig

Offline yogi

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #18 on: April 19, 2020, 02:06:00 AM »
Thanks Craig. I'm using paper in the vise to protect the finished surfaces. My plan is to have the engine done in a "as machined" finish. I'm very picky, especially on aluminum parts, not to make any unnecessary marks in subsequent machine operations. That's probably not the easiest way to finish an engine, but it is my preferred look. 

Yogi

Offline AlexS

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #19 on: April 19, 2020, 10:35:29 AM »
Great work! Looks like art to me your building engines.

Offline Plani

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #20 on: April 19, 2020, 09:24:41 PM »
Very nice Parts  :ThumbsUp:
And great progress!!  :ThumbsUp: :ThumbsUp:
Keep them coming  :popcorn:

Plani

Offline yogi

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #21 on: April 20, 2020, 10:29:49 PM »
Thank you guys for the compliments!  :cheers:

The next series of parts are all relative similar in the way I'll be machining them. I'm also grouping parts together that require the same tooling to be a bit more efficient. I will keep the description to a minimum, but I'll post a picture of each operation. If there are any questions, things are not clear, or this format is not working out, please let me know.

I'm starting with the short bearing block and the support for the swing.

Op. 1: Milling the contour to full depth.






Op. 2: Milling to thickness.






Op. 3: Removing the corner radius on each mounting pad. That's required for the screw head clearance.




Op. 4: Drilling the mounting holes.






Finished parts.




Thank you for following along, and stay tuned for more.
Yogi



Offline zeeprogrammer

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #22 on: April 20, 2020, 11:40:49 PM »
Every time I look into one of your threads, I do it with trepidation.

The finishes you get are so awesome I struggle with trying to achieve that or just going away.

I'm not going away but neither is the struggle.  ;D
Carl (aka Zee) Will sometimes respond to 'hey' but never 'hey you'.
"To work. To work."
Zee-Another Thread Trasher.

Offline yogi

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #23 on: April 21, 2020, 10:20:27 PM »
Oh Zee, the last thing I want is to discourage anyone... I don't know what to tell you. Rigid machines, I guess...  :LittleDevil:

Today's part is the lever.

First, milling one side to full depth.




The part turned around, the second side is finished to thickness and the relief is milled. I drilled and reamed all the way through the stock on the first operation, which allowed me to set the part zero position in the bore.




To mill the slot in the fork, I stood the part up in the vise. That's definitely not the best workholding method, but with light cuts it turned out ok. (I do have a slitting saw arbor on order, as we'll have to do this again  ;))




The finished lever.




Thank you for following along, and check back tomorrow for more.
Yogi

Offline zeeprogrammer

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #24 on: April 21, 2020, 11:19:45 PM »
Oh Zee, the last thing I want is to discourage anyone...

You're not. Your work is inspirational...as is the work (play) of so many members here.

But sometimes...  ;D
Carl (aka Zee) Will sometimes respond to 'hey' but never 'hey you'.
"To work. To work."
Zee-Another Thread Trasher.

Offline yogi

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #25 on: April 22, 2020, 11:05:43 PM »
I understand Zee...

Today's series of parts are the tall bearing block, the two supports for the lever, and the eccenter strap.

These parts are made very similar to the last few parts. First operation is to machine the profile to full depth.








To finish the parts to final thickness, I used a set of soft jaws to hold the parts.








The bearing block and the supports are drilled and tapped.






The finished parts.










Thank you for following along, and stay tuned for more.
Yogi

Offline Craig DeShong

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #26 on: April 23, 2020, 08:16:14 PM »
Very nice work Yogi.  I must admit I’ve never used ‘soft jaws’.  I can see where, for holding odd shaped parts they could be quite useful.  I assume these are ‘throw away’ fixtures you add to the mill vise.  Could you explain how they are attached to the vice?

Thanks
Craig

Offline yogi

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #27 on: April 24, 2020, 12:59:18 AM »
Thank you Craig.
The soft jaws (or machinable jaws) are aluminum jaws that are mounted in place of the hard jaws in the vise. They are getting used up.
I'm a big fan, and use them for holding odd shapes a lot. Another benefit of soft jaws is it lets you locate the work. As you have to machine the jaws, you can use the same part zero point for the part program. Again, that's very handy on odd shaped parts.






Yogi

Offline Craig DeShong

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #28 on: April 24, 2020, 02:33:37 AM »
Thanks Yogi.  I just looked on Mc Master Carr and found them.  They aren’t cheap  ::) but I might get a few pair because I can see a few places in the past where they would have been a real benefit to have.

I’ll probably have an opportunity in the future to need them and when you need them, that’s not the time to be thinking about ordering a pair.
Craig

Online Dave Otto

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Re: Doppelmotor - Double Acting Stirling Engine
« Reply #29 on: April 24, 2020, 02:53:35 AM »
Hi Craig

Check monsterjaws.com they have pretty good prices on soft jaws.

Dave