Brief Description: Wing spar counter-sinking continued #9 FINISHED
About time!!Finished all the counter-sinking for the fuel tank/access panel nut plates. Had to drill out the rivet holes to #40 for the #40 counter-sink. The rivet holes went fast because I didn't need to use a pilot (piece of metal cleco'd and then clamped below the holes) for centering. I highly recommend using a cordless drill vs the air drill as it has more torque and spins at a lower speed which helps elliminate chatter (oblong holes).
Drilling the rivet holes out to #40.
Me and this cordless drill became good friends - lots of holes
