Forming & Roll Taps

Forming taps displace material rather than cutting it, so there is no swarf to clear at all. The thread comes out stronger because the grain flow follows the form instead of being cut through it, and blind holes stop being a problem.

They only work in ductile material - aluminium, copper, mild steel, low-carbon stainless - and they need a larger tapping drill than a cutting tap. Around 5.6mm for M6 rather than 5.0mm.