Originally Posted by MikeAber I tried this yesterday and destroyed a 1/4" 4flute solid carbide endmill. I got about .015" into the case hardened shaft before the end mill edges got too dull to cut. Those rods are really tough. |
You gotttaaaa slow down the rpm (300-500) and feed slowly by hand ...coolant or cutting oil. If you cannot have the beginning of the entrance hole and the last .1 distance at the exit larger than the tap you will find greater problems threading than you found milling. Suggest a 50% thread to take the pressure off the tap. You're right thse rods are really really really tough.
FranH