Opposed Piston Twin, D.Kelley

[Stuart]

Mike I use fusion on a iMac 4 ghz and 4gig of video ram 32 gig of mem but it runs very good on the wife’s Mac lap top with integrated graphics

They only spec a 512 mb graphic card and 4 gig mem

Note it’s Mac and pc

Try microdream they do refurbed windoze laptop and pc reasonable but may have a cosmetic defect but they do give a 12 month warranty

May be worth a look I use a small dell pc for the mach4 setup for my mill

Stuart

[Vixen]

Achim, Stuart,

Thanks for your help and advice. Sounds like a refurbished ex-industrial Desktop PC with an added graphics card, from Microdream, will fit the bill.
The laptop route is too risky, as they are limited to the built-in graphics, which may be inadequate.
Now I only have to find some time and money.

Sorry to have hi-jacked your 'Opposed Piston Twin' thread for the day

Cheers

Mike

[Stuart]

Mike you will be surprised how well microdream pack them up better than the new ones are

Note I am only a satisfied customer

[fumopuc]

Achim, Stuart,

Thanks for your help and advice. Sounds like a refurbished ex-industrial Desktop PC with an added graphics card, from Microdream, will fit the bill.
The laptop route is too risky, as they are limited to the built-in graphics, which may be inadequate.
Now I only have to find some time and money.

Sorry to have hi-jacked your 'Opposed Piston Twin' thread for the day

Cheers

Mike

You are welcome.

[fumopuc]

This project is taking more and more shape.
Just struggling to find a rimfire spark plug cad model 1/4-32 UNEF.
Does anybody know if this is availabel anywhere ?

[Nick_G]

A cheap copy of this

https://oldmachinepress.com/2015/09/26/junkers-jumo-223-aircraft-engine/

.
.
Not a 'cheap' copy at all. - If anything the other way around.!

While I accept that the concept of the Deltic was probably / certainly taken from the Jumo the Deltic was a very reliable engine. The Jumo was short lived and eventually dropped due to reliability issues and constantly trying to eat it's self.!

They probably would have sorted the Jumo issues though if it had been produced at a different period in time without the supply, timescale restraints and resources being needed elsewhere to develop it fully. Also in the few years between the engines massive leaps were made in metallurgy.

Nick 

[fumopuc]

Hi everybody
Some time ago I have discovered the "play botton" in Fusion360. So it is possible to watch your design process in accordance with the growing time line.
Here a sample video, showing my re-design progress of D.Kelley´s opposed piston twin engine. (Would be fun to see the same of Chris´s Marion 91 Steam Shovel design.)
<a href="https://www.youtube.com/watch?v=1rWvxcYeGx4" target="_blank">http://www.youtube.com/watch?v=1rWvxcYeGx4</a>
In the meantime I have also purchased and organized some material and bits and pieces for this model build from around the world.

• A round bar ETG100 (similar to 1141 Stress proof) from Switzerland for the crank shafts.
• Some Italian made piston rings (24x2mm) from Carber, purchased in Greek via ebay.
• The Bosten Gears from US Amazon.
• The valve springs of Stuttgart Germany (Gutekunst)
• The spark plugs and Silicone spark plug boots assembly from S/S R.Sholl.
• A fish tank water pump (220l/h, 12 V)from China.
• Two Swiss sit lock shaft couplings for the flywheels.
• A used motorcycle  twin ignition coil with two high voltage outlets.
• A 3 mm tungsten tig welding electrode for making the pointers from a local store.
• A aluminium lump for making the cylinder block.

Estimated time for the first swarf with this project should be after Christmas this year.
Bill, thanks again for moving this thread.

[b.lindsey]

Very nice animation Achim. This will make a very nice project as I have seen Doug's running in several occasions.

Bill

[crueby]

I like that video! All the times I've gone back and forth in the timeline to make changes, haven't noticed the play button, need to try that! I assume you used the Autodesk screen capture/video utility (forget the name) to get the video?

[fumopuc]

Hi Chris the Autodesk screenrecorder is called 'Screencast' and the records will bei stored anywhere in the cloud.
An advantage of this is, that also mouse and keyboard commands will be captured.
In this case I have used this one
https://www.screenpresso.com/
It is free and does works fine.

[fumopuc]

Happy new year and new swarf again.
I have started to machine the cylinder block.
Must be hidden anywhere in this aluminium block.
This time was also a good opportunity to tram the mill, what I have never done since a long time.
This could be helpful, because the 63 mm face mill has to go in 2 ways over the large surface.
For machining of the first bore for the sleeves, I used the little Wohlhaupter UPA2 again.
What a useful tool against the standard Chinese boring heads.

[Roger B]

Glad to see some metal cutting underway    I will be following this one 

[dvbydt]

Having the courage to even start on this complicated engine, has me wishing you every success. I will enjoy watching!

"Autocourse and Sporting Motorist" magazine (UK) volume VIII Number 32 November 1958, had details of a Cambridge University theoretical study for "A two-stroke grand prix engine". This was to be a turbo charged 750 cc engine producing 500 hp at 15,000 rpm. I have kept this copy all these years in the hope that I might try to build a smaller, simpler model. It hasn't happened  . The article has a very interesting cross section but possible copyright problems has me hesitating to post it here.

Ian

[fumopuc]

Hi Ian, good to know that you enjoy the thread. My extra x-mas holidays are finished now and any further progress will slow down.


This engine you mentioned, is surely also an interesting mile stone in the still ongoing development of the IC engines.

[fumopuc]

Some further pictures of the progress.
Machining the first side with the boring bar in the wohlhaupter was a bit influenced by a collision between the swarf/chips and the bar, because the chips could´t escape.
The other side was much easier, because the swarf could fall down into the already machined side.