I just purchased an 8" diameter rough cut backing plate for my 8" diameter 4 jaw chuck. I found that for a 4 jaw chuck a 5" diameter backing plate is really all that is needed. Since the shipping to return this thing is more than the cost of the plate I would like to modify it by putting it in my rotary table and turning is down with my Bridgeport J head step pulley mill.
The backing plate is 3/4" cast iron. My smaller end mills are about 1/2" length. There is no problem doing two 3/8" passes from each side since final dimension will be done on the lath.
The question is what is the most efficient way to do this. With deep cuts I cant put too much pressure on the end mills So I'm thinking 1/4" end mill is as small as I would have patience for in this hand process. So is it better to take two, or maybe more, 3/8", depth passes with a 1/4" end mill or perform the whole operation with a 1/2" end mill at full depth. Both methods would eventually be finished on the lathe. Should I be looking at doing it with an 1/8" end mill?
The backing plate is 3/4" cast iron. My smaller end mills are about 1/2" length. There is no problem doing two 3/8" passes from each side since final dimension will be done on the lath.
The question is what is the most efficient way to do this. With deep cuts I cant put too much pressure on the end mills So I'm thinking 1/4" end mill is as small as I would have patience for in this hand process. So is it better to take two, or maybe more, 3/8", depth passes with a 1/4" end mill or perform the whole operation with a 1/2" end mill at full depth. Both methods would eventually be finished on the lathe. Should I be looking at doing it with an 1/8" end mill?