dmcnally
Aluminum
- Joined
- Jun 12, 2012
- Location
- Lompoc, CA
I have an older CNC mill with NMTB40 tool holders. The mill has a manual drawbard. I've been using er16 collets in collet chucks with 1/2" shanks for drilling. Swapping the collet chucks is a lot easier, faster, and cheaper $$$, than swapping the NMTB40 tool holders.
I bought 5 er20 collet chucks with 3/4" shanks and I'd like to use them to hold my end mills (1/4, 5/16, 3/8, and 1/2), edge finder, and 90 degree chamfer bit. I'd like to swap the collet chucks in sort of a poor mans power drawbar.
I experimented with the 1/2" end mill. I was trimming (facing) some stock to get it to the proper size. I zero'd the 1/2" end mill and then attempted to trim 0.100" off the top of a piece of stock. This setup trimmed 0.110". I tried with a 0.020" cut and the resulting cut was 0.024".
I'm assuming the difference is due to collet flex. Does that sound correct, or am I way off base (i.e. clueless)?
I'd like to use the collet chucks for the poor mans power drawbar, but I need to have predictable depth of cuts.
Any advice would be greatly appreciated.
thanks,
Dave
I bought 5 er20 collet chucks with 3/4" shanks and I'd like to use them to hold my end mills (1/4, 5/16, 3/8, and 1/2), edge finder, and 90 degree chamfer bit. I'd like to swap the collet chucks in sort of a poor mans power drawbar.
I experimented with the 1/2" end mill. I was trimming (facing) some stock to get it to the proper size. I zero'd the 1/2" end mill and then attempted to trim 0.100" off the top of a piece of stock. This setup trimmed 0.110". I tried with a 0.020" cut and the resulting cut was 0.024".
I'm assuming the difference is due to collet flex. Does that sound correct, or am I way off base (i.e. clueless)?
I'd like to use the collet chucks for the poor mans power drawbar, but I need to have predictable depth of cuts.
Any advice would be greatly appreciated.
thanks,
Dave