SPEED TIGER Carbide Square End Mill - 4 Flute - IPVE1/4 4 (1 Piece, 1/4") - Unequal Flute Spacing & Helix Design - Anti-Vibration - for Stainless Steel - Mill Bits Sets for DIYers & Professionals

4340 36 rockwell. 10000rpm 60ipm .400 depth .017 step over On a desk top cnc with a iso20 er20 220v spindle. Endmill works great. Thats .400mrr and around .002 chip load.

I've gone through my share of endmills and they always burn up as with a 24k rpm spindle, going less than 3000RPM is not easy as the torque available is almost nil. I bought one of these for hardened steel and stainless steel I needed to mill and this endmill I've got actual cutting time so far 6 hours contact in hardened steel and 11 hours in stainless steel total and this still cuts like a hot knife through room temperature butter. 3137 rpm at around 650mm/min works great in either metal. 1st order from this company and won't be my last, in fact all my purchases will be from this company.

Worked great I even had depth as deep as it could go n it worked fine actually bought two more after that

It works ,the perfect tool

Used this end mill in a router table to mill rectangular holes out of a casted aluminum (2.5mm thick) enclosure. Cut through it like butter, while maintaining its sharp edge even after repeated use.

Herramienta de corte para aceros de alta dureza (4340-300M),con resultado de gran rendimiento y duración. Muy buen producto.

Great for the home machinist and work also !!!

I use this as a router bit and it's incredible. I've routed fir, oak, mahogany, aluminum, brass, and thin mild steel. After 3 months of occasional use (only about 5 minutest a day averaged out) it's still about as sharp as new. I use it primarily to open up strike plates for customers whose doors aren't closing properly and it's been a godsend. Try it out; what have you got to lose?