Laminar Flow Engine completed!

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lazylathe

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Hi All,

I have finished my first Stirling engine! ;D
In fact my first engine that actually functions, so it was a great success for me.

I started by watching a number of Stirling videos on utube to find some basic ideas.
Something simple to start with that i would be able to complete by myself with my limited knowledge.

This was the drawing that i made and based the engine on.
P1020509.jpg


From there i made the first few basic parts.
Very easy machining here, i did not really have any fixed dimensions except for the length of the piston con-rod and the diameter of the test tube.
I learnt how to use my boring head and even mounted it in the lathe using a 4 jaw chuck to line up the two centers!
This was the first batch of parts i made.
P1020372.jpg


And a rough fitting of the parts to see what it would look like.
P1020373.jpg


And a close up of the graphite piston.
P1020374.jpg


I then needed to figure out how to attach the test tube to the main part.
I decided to machine a part and bore it out to the diameter of the test tube.
P1020465.jpg


I would use a high temp gasket sealer to create an airtight seal.
Here is the base assembly with the test tube.
P1020467.jpg

This part was also quite hard as i had to drill four holes that lined up correctly and then tap the main base with a 2-56 tap.
The bits after drilling and tapping.
P1020469.jpg

Quite nerve wracking but i made it through and it all fit together well!
P1020468.jpg


I then forgot to take pictures of the stand...
I took a piece of hex stock and turned the top down to 8mm and drilled a corresponding hole in the main unit.
I was going to try my hand at threading on the lathe but thought twice about it...
That can be done on some practice bits later!
The stand is going to be loctited into the main unit.

I then went over to my mill and using an 8mm round nose mill i milled some slots into the stand.
Set the work up at a 2degree angle and milled all 6 sides.
It turned out okay i think.

Lat night i fashioned a wooden base for it out of Jatoba that is edged in Zebra wood.
A few coats of lacquer and it is nice and shiny!
I am using a jewelers alcohol burner with denatured alcohol as the fuel.
So far it has run for an hour non stop and there is still a lot of fuel left!

This is the finished engine.
P1020505.jpg


P1020504.jpg


P1020506.jpg


And video of the completed engine running.

[ame]http://youtu.be/pGP4AaKvfnE[/ame]

I am thinking of making a larger diameter flywheel out of something a lot lighter.
It might go a bit faster, although i like the slow and steady way it runs now!

Hope you enjoyed the post and the journey with me!

Next project is Jerry Howells Sideshaft vacuum engine!

Andrew
 
You have a heat engine but Stirling is something else. Laminar engines are, "Fun in 15 parts or less"! Nice desk top display. You can try some coarser/ looser packing in the tube and note the changes in speed. You're on top of it Andrew, g-luck on the Howell engine. Dave
 
Hi Andrew;

Looks and runs great, I expected nothing less :bow:. Now explain to me how it works. :shrug:

Peter
 
Thanks guys!

I have taken out all references to Stirling engines....

Andrew
 
Looks good and seems to run really well. Congratulations

Navigator
 
I posted earlier but my post disappeared into the internet file 13.

Congratulations. Those can be very frustrating to get running for the simple reason that there is nothing to check or adjust.

As Dave pointed out, the heat exchanger has a major effect on speed. Steel wool works better than SS wool because it has better heat transfer. The grade (0000 - 3) also changes the speed as well as the density. Have fun with it because it is so simple it shouldn't work.
 
This would be awesome to build! Where did you get the graphite for your piston and the glass part that the piston rides in? I found a site to buy the Pyrex tubes but not the other piece.

I love the physics that are involved with these engines.
 
Thanks guys!!

I cheated a bit on the graphite piston and tube....
I bought a airpot to use! ;D
It comes with the graphite piston and the tube.
Just trim to tube to length with a diamond disc and you are good to go!

I can find smaller diameter graphite around me but no real big bits.
Have to order them from the States which gets quite expensive.

Andrew

ps: if you go to the airpot website you can request a free one as a sample! Only in the States...
 
nicely done I searched for airpot but got no were could you post a link plz, also were did you find the nice burner?
Thanks for showing
Dave
 
The burner was bought from a local supplier of jewelry supplies.
It is just an alcohol burner that i use denatured alcohol in.

It has a cap so that the liquid does not evaporate.

Andrew
 
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