Drilling Hardox

[makulax]

Hey all!!

First post here =) Need help figuring out the feedrate and RPM for drilling and tapping a M12 tap on a machining centre. Have tried with low RPM and quite low feed, but no success.

[hoidahl]

we have machined hardox 450. Its about 45 rockwell c. We have drilled it with a carbide drill 200 sfm and .0055 ipr. Milled counterbores with variable flute endmill 325 sfm and .001 ipt.