@vince posted Here about Steel
in 0.250 lakeshorecarbide fireplug
80ipm, 10krpm
0.0008 maximal chip
0.250 adoc 0.010 rdoc
He has another thread for titanium here
8mm CP1
Lakeshore 250 Fireplug
Lakeshore 250 4 flute ball
Followed a 0.0008 chipload for 0.0625 roughing, then 0.002 chipload for ball finishing