12 years ago
I was drilling some 1/2" holes today in some 3/8" mild steel today (for the
base clamp of a drill press stand I am putting together), and was wondering
about drill bit temperatures.
I'm using "Rapid Tap" as a cutting fluid, and when it starts to smoke off, I
stop and put some more on. I am keeping my chips/spirals from getting to
the straw colored stage, and measuring the bit (HSS) temperature with a
non-contact thermometer tells me that my bit is at about 160F.
At what temperature should one limit a HSS drill bit to in order to prolong
the life of the bit? Does anyone have any numbers?