[ypmcnc]

Hi Gent and Gentents!

I'm newer to machining and I'm trying to accurately ream a .407 hole in aluminum about 2.3" deep. I have an LMS x2 mini mill converted to cnc that although has an upgraded motor, still struggles with a 9.7mm drill bit. I was wondering if I could spot drill, drill a 1/4" hole, then use the 9.7 drill. Would this still make an accurate hole? I need the location to be within .0005 (which the machine is capable of). Any input would be awesome! Thanks.

-Will

[routalot]

Try it on a piece of scrap?Doesn't appear to be an easy task and it presumes the drill bit is exactly what it claims to be.Do you have a small boring head?Again,a test cut would be wise.