I hold drill bits up to the screw and find one that just covers the
skinny shank part, but not the outer edges of the threads. A thicker
drill and the screws won't hold. A drill bit thinner than the inner
diameter of screw, and you can't get the screw screwed in. That's
perfectly clear, right? When in doubt, start with a smaller bit, and go
bigger only if you can't get the screw screwed in.
:)
Steve Barnes sailing a Capri-16, #74, no name yet,
and selling a WWP-14, Popeye, #561, in San Diego.
OLDSURFDUDE