Pot-Bellied Backyard Stirling Engine

Home Model Engine Machinist Forum

Help Support Home Model Engine Machinist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

IronHorse

Project of the Month Winner!!!
Project of the Month Winner
Joined
Mar 3, 2008
Messages
243
Reaction score
20
Well I woke up one day late last year yearning to build a “whacky engine”. You know the kind; Large, made from reclaimed parts, lots of pipes and spinning things and no bling. I started with the Moriya engine plans. I like this design because you can scale it up or down and it always works. Basically it is a 2X scale engine with water cooling. I modeled the engine in Pro/Engineer first to make sure everything worked and to work out all the dimensions.

ratair-mech4.jpg



I found this “Made in Taiwan” miniature pot-bellied stove at a local Antique/Junk store. I am sure it was meant to be purely ornamental, but with working dampers, grate, ash tray and provision for a chimney, it was perfect! I fabricated a chimney up out of some pipe and sheet metal and mounted the engine to the top. The engine will run at 400Rpm with a nice fire below.

Main-1.jpg




The cold cylinder was made from 2 pieces of aluminum tubing. I machined the inner tube so it would fit inside the outer tube, and then “hogged out” the inside of the outer tube. I then sandwiched them between two thick plates.

PC090143.jpg



The power cylinder is mounted in what I call a “flying Flange”method and the piston inside is from graphite.

P1050013.jpg


The pump is basically the same as the one used on the Ericson Hot Air Engine, with a few minor modifications.


PC090141.jpg





The brass water reservoir is a part I found in the garbage at work, I think it is for a de-humidifier. It had a float attached to one end,which I cut out and soldered the copper pipe to. I also added a small “Cooking”thermometer so I can monitor the water temperature.
P1050014.jpg



Although Hot Air Engines are inherently safe, I made apressure relief valve just in case. I figured that since this is water cooled,and there is only a gasket to seal it, If ever there was a leak of water into the hot cylinder, I would have a sealed Boiler! This would be very dangerous,so I made the valve to be on the safe side.

PC090150.jpg


It ran the first time real good. It will run at 300RPM witha propane torch on full, but it will run forever at 100RPM on the smallest flame (¼”) I can get on the torch. There may be some more power available to run a small generator,but first I am going to do a propane conversion so I can run it inside this winter.
P1050018.jpg

P1050020.jpg



PC090131.jpg




And finally a Video. It was -4Deg C this morning when I made this.



IronHorse
 
Nice job IronHorse. Thm: The Moriya was a great choice to upscale. Mine has been running great for a few years now. Thanks for the pics and video.

Craig
 
That is one unique neat engine. :)
Ernie Johnson
 
Nice work + you've already got the stove to sit around and watch it run;)

Congrats

Phil
 
Iron. Congratulations on a win, a very nice engine indeed which has a wonderful sound.

Anthony.
 
This looks great.

Can you give a link, where the original drawings are, which you used and
also give the dimensions you used?

-hv
 
Hopefully One Day.....Great Engineering Congratulations.:)
 
Well done.
My original scale Moria has been running well at shows for several years.
Perhaps a fan at ( or in place of ) the flywheel would spread the potbelly heat around your shop.
Fastfreddy
 
Have you powered anything from the flywheel yet?
It should be able to generate power but it is beautiful on it own, Well done
Chers Frans Cubitt
 
this is possible you can post the plans, thanks.
 
That is truly awesome! I would be interested to know how much electricity this engine could generate.
 
Iinnovative work, it's a pleasure to watch it in motion!
 
Good thought. I am just finishing up a model Bremen Walking Beam engine and it also has a pretty substantial closed system construction. I have always been a little concerned about water leaking into the "boiler" displacer cylinder, but never considered making a "bomb" out of the engine. I believe that I will install a safety valve.

Thanks -- a beautiful job on that engine.
 
Hi,

my Friend just bought a factory made quite similar engine.

It is available here.

http://www.hyporex.ca/big-stirling.php

It seems to be good.

---

I think that your 2X size engine should be tested to find out how much power you can generate.

If run by solar energy, using concentrating mirrors, and burning wood, it could make a way to generate electricity in remote areas and in developing countries.

---

Has anybody tried to combine several engines like this on the line (3-6 cylinder...) to see, if the efficiency could be preserved so that a real home made power station could be developed?

with best,

-hv
 
Back
Top