I just dip them in a can of white paint that has about an inch or so of paint in it. Once it stops dripping I fling the excess off (out of doors) by holding the prop as if it were a paint brush I had just cleaned and I'm trying to shake the water out of it. Do one tip, loose the excess paint, do the other tip, put it aside to dry and finally recheck the balance. This is by far the easiest method I have ever used. No measuring, no taping, no priming, no overspray, no cleanup. If it's out of balance a little dab of paint will do it.