PhillyAlchemist

15 minutes ago, anvil said:

More to the point than definition of terms is you anneal and normalize from "cherry red", not a yellow. This is called "critical temp". Critical temp is just after it loses its magnetism.

Also, bring it up to "critical temp", dont bring it down to "critical temp'. This means do it on a rising heat

So what happens if I anneal from above the critical temp? I though the purpose of annealing was to remove the stresses from the metal by bringing it above the plasticity state. 

24 minutes ago, pnut said:

Cooling it slowly in vermiculite is annealing the stock and should make it easier to drill. What type of steel is it? Some steels are air hardening.

Pnut

It's 5160.

I didn't have any trouble with the first knife I made but the last several have all given me trouble when I go to try to drill the pin holes. My process is to forge the shape, bring it back up to a yellow heat and "normalize" it in vermiculite. The next day I do my basic shaping and try to drill the holes but I've thrashed several drill bits now on clearly hardened metal. I thought the normalization step would reduce the hardness of the metal to make it easier to drill. Am I doing it wrong? Any advice is greatly appreciated!