drilling 17-7 sst

[Porkbun]

ok i got a .042 hole +.002/-.000

im drill wit a .041 carbide drill with a .125 shank ,my hole after the op is coming up .045

i got a spot for the drill

 

any ideas? i checked run out,chips,drill

could the rpm be a factor on it? s22000 with a .01 chip brea

 

oh yeah its running on a willemin 408b

 

Rich

Wightmaneng

mastercam x2mrs

[Michael Sullivan]

RPM is a little high from my calculations. What feed rate are you using?

[bogusmill]

I just drilled some .02 X .6 deep & .03 X 1.0 deep today. Not much there in the way of flutes to contain chips so I used pecks of .005 retracting completly out. Holes came out great in aluminum. Hope this helps.

[chris m]

I'm thinking I'd try 9095RPM [100 SFM] and see what happened