Stirlingengineforum.com

Ian S C wrote:Conner, you could try thinning the hot cylinder, at the hot end to say 1 mm to 1.5 mm thick, the thinner it is the easier it is to heat the air inside.
Ian S C

Thanks Ian, I'll give this a go.

Aviator168 wrote:I see the cold piston sticking out. Why is that?

The Pistons are just shorter than the cylinders, so each one sticks out by 15-20mm at the end of each stroke. I did this to encourage air seal, but I may halve both their lengths in attempt to reduce friction/weight. They're currently about 57mm each.

Update - Fitted a much smaller capacity transfer tube as suggested. I also eliminated the dead zones at the end of the cylinders. It Still wont run, but feels closer & will go about a couple of rotations before stopping in a springy fashion. The new transfer tube isn't so small that it's restric...

Connor, best not to use steel against steel for cylinder and piston, cast iron is the only metal that can be run together without undue wear, or high friction. A polished steel bore, with a brass piston would be ok, or a brass tube with a steel piston. Ian S C Thanks Ian, in that case I'll have to ...

There is a chance your engine will work by going with a much smaller tube. Better yet, replace it with a metal tube. TDC -- Top Dead Center. When the piston is at TDC, make sure there is no room left in the cylinder. Also, does your cold piston lag the hot piston by 90 degree? Your design is a typi...

Connor, start with the hot cylinder. (1) I'd take the out let out the side at TDC, The piston should have an extension on it, made in a similar fashion to a displacer, this is called a Heylandt Crown, the heating takes place at the top end of that, and the hot cap should be about .25 mm thick, more...

Aviator168 wrote:BTW. Why did you use copper for piston and ss for cylinder? You should use the other way around.

Unfortunately there wasn't any square Brass bar that I could have used as the support, only cylindrical brass bar.

I wouldn't have TOTAL dead volume greater than 20% of displacement. Look how small this tube is. https://www.youtube.com/watch?v=NF4qvpR8RvY Ah right okay, I'll strip the current transfer tube off of it and install something much smaller. Not small enough though for it to restrict the flow however....

Aviator168 wrote:So the displacement off each cylinder is about 6cc. What is the dead volume of the transfer tube?

I hadn't taken that into account. I believe it's also approximately 6cc, maybe just over. Is this too much?

Hi, I'm new here. I've tried to take in as much as the forum activity as possible, but please let me know if I've posted wrongly. I've machined an Alpha Stirling Engine for a college project, but I'm all out of ideas on getting it to work. Can anybody help me? please! I've attached a photo.. I think...