Cutting speed is how fast metal is removed, isn't it? Anyway, since there have been no replies to my averages idea I threw together something quick, you can check it out
here.
I filled in the grits for the Nortons and DMTs and also speed and hardness for the Nortons. You can't fill in any data for the Nortons as they are the baseline data everything else relies on.
Any feedback at all would be appriciated.