At 09:23 PM 6/11/2013, Jeremy Stovin wrote:
>Why can I not get a screw or drill in this floor? It just stops.
>Metal, self tapping screws, nothing.

Forgot to say, your final drill for a self-tapping screw should
usually be the same or larger than the diameter of the thread roots
on the screw.  Easy selection method is hold the drill and screw
together.  If you can just see the sides of the drill past the solid
part of the screw, just right.

The hole in what you're fastening down, though, should be larger than
the overall screw diameter.  Otherwise it will hold the two parts
some constant distance apart instead of clamping them together.

Yours,
David