12-22-2013, 08:39 PM
Today I made the blank for the 70 tooth gear I need. I found a 130mm piece of unknown steel, something that was at one time an arbor for testing spindle runout on some machine. It's soft enough that my bandsaw was able to cut through it and when I went at it with carbide insert tooling on the lathe it machined just like 1018 CRS.
I got the 126mm O.D., the 11mm width, the 0.9mm x 60mm boss and the 20mm bore done. Now I've got to figure out a good way to broach the 6mm keyway. The piece is still sitting in the chuck of the lathe, so if anyone has a good idea I'm listening. My first thought is for me to take a 1/4" square HSS tool bit and grind the tip of it to 6mm, then mount it in a homemade boring bar I have to holds 1/4 tools, center it (somehow) and take a lot of .001/.002" passes on it with the spindle locked. Centering would be the hard part. Got ideas?
I got the 126mm O.D., the 11mm width, the 0.9mm x 60mm boss and the 20mm bore done. Now I've got to figure out a good way to broach the 6mm keyway. The piece is still sitting in the chuck of the lathe, so if anyone has a good idea I'm listening. My first thought is for me to take a 1/4" square HSS tool bit and grind the tip of it to 6mm, then mount it in a homemade boring bar I have to holds 1/4 tools, center it (somehow) and take a lot of .001/.002" passes on it with the spindle locked. Centering would be the hard part. Got ideas?