Boyd's Tin Can Stirling Hot Air Engines

Phase 2

Some alterations were made.
The old copper pipe was removed and a new style power cylinder and piston was installed
.You can see the new style cylinder here

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I added a 90 degree elbow fitting to the back of the new cylinder

The water cooler tin can was hole sawed out and fitted on the displacer.
Then it was attached using red hi temp silicone sealer. You can get this at any auto parts store

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I used a U bolt from Orchard Hardware for mounting front and back.
Copupling nuts at the bottom with flat head machine screws will mount from under the wood board when mounting.

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Picture of front U bolt setup

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Ready to mount to a board.

Here it is mounted to a shelf board.

Close up of the power piston just hanging out just a little.
I used a rod end from a hobby shop on the power piston.
Now for the fly wheel!

Phase 3

Almost done. In this phase (at the end) I fired it up. It would make about 3 to 4 cycles and then stop.
More on that later!

I used tie rod ends from RC planes to make the connecting rod

I used RC rod ends and clevises to make the displacer rods. I had to support the rod coming out of the displacer
cylinder with a brass rod. This made the rod go in and out easier without binding.

A better view of the same rod

As I said earier, I fired it up and it would go about 3 or 4 cycles and then stop. I removed
the piston rod from the flywheel crank and turned the flywheel around creating "cycles".
The piston would push out and pull in just as it should, but I feel it should have a little more power.

Problem?
I think the main problem is not enough heat getting to the rear of the displacer cylinder.
As you can see I have no "hood" around the displacer cylinder to direct the heat evenly around both
sides of the cylinder (outside). I think if I fabricated a hood it would heat more evenly. I was able
to get more power by moving the Sterno can back and forth or from side to side. This heated the engine on
both sides more, but even would be better. (no I didn;t use the entire can of Sterno. That is an enpty can with the lid on it.
The Sterno was placed on top of that to get the fire closer to the cylinder.

The second proplem is......Tha big honking "U clamp" in the rear. I think it might be sucking up a lot of heat. Sort of like
a heat sink. I think I might move that forward all the way to the water tank as close as possible. That might help a bunch also.

Still over all. 4 cycles is not too bad for a first attempt!

Phase 4
The Final Phase?
"I've got to have more power!"

OK, moved the mounts (pipe clamp) forward in front of the power piston exit and made a fire box.
The fire box was made from another can (like to stay with the program) and installed.

Ran great for about 2 to 3 minutes then everything broke loose....well exploded to be exact.
You will notice the small can of sterno on the left of the photo above. That can had it's lid on
and sterno on top of it to place the fire closer inside the firebox. Very bad idea!
After running about 2 to 3 minutes that can heated up (DUH!) and exploded. That is why the lid is off
and the fire box is turned a little sideways. Didn't even see that one coming! Can was still on fire be it almost out.

Notice I thoiugh about removing the cap of the water tank. I though to myself.....
better remove that cap, don't want this thing building up pressure or steam and blowing apart!
Almost had it right!

Firebox removed from rear of engine

Still it ran for some time there. I need to work on the timing a little and a new way to deliver the fire into the fire box.

That's it! I don't see a PHASE 5!