Well I'll respectfully disagree with Warp as to where to measure pitch. As to painting, I painted the whole forward face of my prop with urethane, then sanded smooth and polished and dynamically balanced.
Guy Buchanan
San Diego, CA
Deceased K-IV 1200 / 912uls / 70" Warp 3cs gebuchanan@cox.net
The placement of the protractor really doesn't matter.. as long as you place it in the same relative position on each blade. The difference of comparing that angle set between aircraft will be dependent on the same placement. Due to blade twist, the angle used at the tip will be different than the angle used 6 inches from the tip, for comparson purposes.