Well, you guys warned me.

I have not put a flat spot on my Neu's shaft...yet. I have been bashing for months with a tight grub screw and loctite until today. One minute into a bash with an extra 3.7 volts and I lost the pinion. Luckly no damage to the spur.
I talked my wife into giving the Dremel (one of my Christmas presents) early. I'll be grinding.