RE: How are you drilling your props
Great Planes has a metric prop reamer that reames 1/4",7mm,8mm,and 10mm holes. Tower Hobby sells it for $14.49 (pt #GPMQ5007) and also has an inch size reamer that does 1/4",5/16",and 3/8" holes (pt#GPMQ5006) also @ $14.49. I have them both and they work well.