Everyone has that problem. You have decide what is right for you. I think I wound up taking the CS bit and putting it on my deburring tool and hand cranking that. Not show quality, but certainly acceptable. Those rivets were a little difficult to set too, can't get the head of your flush mount rivet set in there. I wound up using a flat piece of steel and using that between the rivet and the flush mount rivet set.
RV-14A empennage, wings
2018 dues paid