I very rarely run stainless but right now I have a large order where I need to take about an eighth inch off 4 inch square plates. I have a couple 2" 4 insert face mills, one with square inserts at a 45 angle and the other just straight rectangles. We had our tool guy recommend the proper inserts but the speeds and feeds he gave us are just not working no matter how much I've changed them the inserts still become unusable from the corners chipping off after just 4 or 5 plates and the insert cost is starting to add up. Can anyone give me some idea of what speeds to start with that I can tinker with? And should I use coolant I've tried it both on and off we don't have the best coolant set up just spraying the endmills with generic TRIM E206. I'm slowly getting somewhere but I'd rather not waste any more time or inserts.