Will wood scratch 904L steel?

[J!m]

I didn't read all the posts but here's some food for thought:

Grinding wheels work best when they break down during grinding. Too hard a wheel is not as effective at stock removal.

Then there's the species question. Probably not black walnut if from Central America. And it's not Peruvian either as I used a lot of that in my guitar making.

Then there's another thought: black Palm wood. It is black from the fine black sand that gets caught in the wood as it grows. That stuff will destroy a carbide blade faster than dropping it on the concrete.

Anyway, maybe you can remove one side from each watch holder. Then it doesn't have to go over the wood.