Knurled or plain GN1 crank?

When you first hit it with the journal, the sparks will fly.... VERY shortly after that the sparks will subside.

At that point the polisher is pretty much done eating.


So to answer our question, the workpiece will decided how much you polish.
 
Having an automotive machinist background, I'd tell you hit a shop that does nothing but grind/polishes cranks.
 
Top