Pilot and Shank Drill Sizes for Blind Fastener Removal
PILOT DRILL SIZE
SHANK DRILL SIZE
0.0980 (No. 40)
0.1540 (No. 23)
0.1285 (No. 30)
0.1890 (No. 12)
0.1590 (No. 21)
0.1730 (No. 17)
With a round carbide burr, grind an
With a hammer and minimal size
indentation in the center of the fas-
punch, sever the head and drive
teners to be removed.
out the shank and blind head.
Using the pilot drill and a drill guide,
(b) Perform the following steps to remove
drill on the centerline of the fastener
fasteners that turn when drilling. Refer
to be removed. Drill to below the
Using the shank drill and drill guide,
drill in each fastener hole to the
depth of the pilot hole.