(12-22-2013, 09:01 PM)wrustle Wrote:(12-22-2013, 08:39 PM)PixMan Wrote: 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?
Ken,
Couldn't use scribe a centerline on the tool and set in your toolpost?
To get it nearly exact, place a tool you know is on center in your tool post, then use it to scribe a line the face of the gear using your cross slide (spindle stopped of course). Place your gear cutting tool in the tool post and match up the scribed lines.
Just be sure to NOT move the chuck during any of the process.
Now.....why can't you mill the teeth in your mill?
Program it, go have a beer or two or three, and by the time you come back it may be done!
Merry Christmas!
Russ
Ok, just realized you wanted to BROACH it!! Doh!
Thought you wanted to cut the teeth cause you texted me about it earlier today.
Does it have to 6mm? I think I have 5mm broaches. Will check at work tomorrow.
Later,
Russ
PS, if I do have a broach, it would take about 5 minutes start to finish in my press.