Stirling Engine Project Status - gettng bags

I finally got a response from the KNF and they are processing the sample request.

I downloaded Sketchup from Google and begun making a 3D CAD model of the design. I should have model done this weekend. For now my priority is to start fabricating a second cylinder and piston assembly, so I will be ready when I get the bags for the seals. Also assemble the cam case. I am using acrylic for the heads for now, so I can see the top of piston. If the seals work, then I will switch to aluminum and tap them for 1/4" pressure hose connections.

I work on the machining in the evening because it makes noise and switch to assembly and software at night. I will try to take some pictures this time as I make the second set. The 3D modeling really helped, by showing where to put the head bolts, so they don't get in the way when assembling the cam case. There is no crank in this design, only a cam. This makes it possible to have up to four cylinders, two hot and two cold in a single radial plane. The shaft is straight through, The plan would be stack four packs to increase the total power of the engine. The current heads are just flat pieces that can be shared between adjacent layers of the stack.

The goal here is to keep the tops of the heads as flat as possible to keep the heat exchanger components simple to apply.

Initial testing will be on the minimum two cylinder configuration using low pressure air as the working gas. Once I up the pressure, we will need the opposing cylinders to balance the forces. The piston is > 3 sq in, so 100 psi is over 300 lb force on the cam. My main problem is providing support for the cam follower, so it doesn't jam or bend on the curved portions of its travels. I think I have that problem solved, just more stuff to build.

I am not have mentioned that assembling the seal is quite difficult. The bag material has to be stretched from under 2" in diameter over the outside of the cylinder which is 2 1/4 diameter. I will have to do some heat forming of the bag for production, so it all goes together much easier.