kloner
Aerial DP
what happens is if you put a washer on top, it runs into the same problems as the nut is it can't get over the 6mm shaft. being nylon it could squeeze, but most likely not true. if you use an 8mm washer, it'll fit top or bottom cause it'll go over that little hump thats left above the prop, but i'd use em under where all of the washer sits on all of the shaft.