Moriya Fan progress

[tailwheeldriver]

Hello all, I think I've finally got enough parts going to share my progress on James Senft's Moriya Stirling fan. This project rather stalled for a while so I"m thinking posting progress updates will keep me accountable to get parts done.

Some parts I"m making two of, either because they're very easy or because I feel I might mess one up in some way. Feels like less of a setback than starting a part totally over from scratch.

First up is the displacer, made from .040" tubing from an old tent awning. I held it very gently in the collet chuck and bored the ends. On the second one I dared to turn the outside, which resulted in only a little chatter. I probably won't notice it running any different but the second displacer turned out 2 grams lighter than the first.

My first time trepanning anything on a lathe is to relieve some weight from the top cap on the displacer. Takes a lot of relief on the tool for a less than 1" diameter.

And the end result of that part:

 

[tailwheeldriver]

Next I thought the crankshaft looked like fun. I want this engine to be sort of polished up, but I have little experience in that area and will endeavor not to fuss over it to much. Should be some good practice for me though.

Having said that I cheated on polishing the crankshaft and surface ground the parts.

Also shown are the bearing holders. I didn't have any 1/4id 1/2od bearings but found some 6mm id 20mm od bearings and went with that. That did necessitate altering my shafting if it was to be a 1/4" pressfit into the crank and 6mm for the bearings. I could probably turn it down fine, but I"m always needing an excuse to use the punch grinder.

I got so into figuring out how to fit things on the grinder I forgot to get a picture, but here's one of getting the footstock to the right height for the longer part of the crankshaft.

Then I went on to the displacer conn rod. I milled the stock to size, center drilled the bottom and tapped the top. Then off to the 4 jaw to turn down the center. One has now been back to the mill to finish the clevis on the bottom, then I"ll make the top to bolt on and drill/ream that for 0.251".

More parts soon, thanks for looking!

 

[tailwheeldriver]

Well the cold end top-cap is complete, along with an extra. The cold end itself is milled to size and bored 1-1/16, but needs the fins turned on it next. There's so little to hold onto I think I'll make a quick fixture for turning on the lathe rather than try to make the 4-jaw work for this. I also didn't have any 3/16" stock handy so I had to turn down a length of 1/4" for the cylinder studs.

Two side plates have been made from a somewhat rough plate of 1/8" aluminum. Rough cut on the plate shear and filed around the edges.

Finally enough progress to start assembling a few parts; the crankshaft is complete. Somehow one hole turned out too large and I had to red loctite it together. Must have let the chips build up in the reamer.

That's all for now until I get the fixture made for the cold end.

 

[tailwheeldriver]

Well work and an imminent winter have kept me out of the shop quite a bit lately, but I made some time to build a fixture and turn the fins on the cold end.

I didn't get any in progress pictures, but here it is after turning at 1500 rpm. I have made my peace with HSS part off blades, and can sharpen them pretty well, but for deep slots like this nothing beats the chip ejection of a carbide insert part-off tool. I'm convinced if you're getting started with insert tools, or can only afford one carbide insert tool, make it the part off blade. Everything is so much easier in the shop; even out of the shop, food will taste better, and colors will be brighter because you have a carbide part-off tool.

The end result, deburred and ready to go. I had time to size a bunch of other stock to size so hopefully in the next week I'll have some finished connecting rods and baseplates finished.