Monday, February 09, 2009

Another 32 hr weekend.

I finished the shells for the regen motor. So I have the inner core and the outer shells almost all done. All I have left to do is cut the cooling channels in the inner core. I only made one minor error in the set of pieces and I fixed that with some valve lapping compound and 3 hours of elbow grease. Based on what I can see and measure the worst case gap between the shell and inner is 0.005” Most places its tighter than that.

If all goes well I’ll start cutting the cooling channels Monday night. And I’ll have it ready to test by Friday.

Whine the weekend was spent machining one can never seem to avoid writing software ;-)

I wrote a lot of software this weekend. I have several good programs to convert CAD drawings into instructions for the milling machine, I have not found a good one for the Lathe. I tried a demo of an expensive lathe cam package and it crashed on about 50% of my drawings. So if the demo crashes how good is the production S/W going to be? So I wrote some code that takes the line geometery for the part to be made and makes lathe G code. It works for both inside and outside roughing and finishing. Some day I’ll even put a UI on it so you can change things like tolerances and mode without recompiling. CAM software for the lathe is something I’ve been meaning to do or research and buy for a long time, I just got tired of measuring a bunch of points and shapes on the cad drawing, moving them to excel then doing a bunch of geometry calcs in excel, and finally hand translating them to g code in a text editor. My one macining error looks like it was a transposition of two digits on the coordinate for the center of an arc. I’ll take pictures of the parts and maybe even a short video showing how it all goes together.


Anonymous said...

Just like a long RV trip, the destination is great, but the journey is the best part. Thanks for the frequency updates!

David said...

Sounds like great progress. Programming can be a lot of fun if it is an interesting project or help in some way toward your goals. If you need a hand I'll be happy to play around in some spare time.

The next construction step will be very interesting. Thanks for the updates.