wrote in message
ups.com...
A drill gauge is inexpensive but you don't need one.
Hold the screw up and look at how much metal is under the treaded
parts
and choose a bit closest to that size or just a little under.

That makes sense.

You can
use a lubricant on the screw to ease installation, beeswax, an old
candle or bar soap.

I'll try to remember that, happen to have all three.

Here is a chart from the web.

Wood Screw Pilot Hole Size

Screw Size Hard Wood Soft Wood Countersink Size
Tapered Bit Straight Bit Tapered Bit Straight Bit
2 3/32 1/16 5/64 1/16 1/4
3 7/64 5/64 3/32 1/16 1/4
4 7/64 5/64 3/32 1/16 1/4
5 1/8 3/32 7/64 5/64 5/16
6 9/64 7/64 1/8 3/32 5/16
7 5/32 7/64 9/64 3/32 5/16
8 11/64 1/8 5/32 7/64 3/8
9 3/16 9/64 11/64 1/8 3/8
10 13/64 9/64 3/16 1/8 7/16
12 7/32 5/32 13/64 9/64 7/16
14 1/4 11/64 15/64 5/32 1/2
16 9/32 3/16 17/64 11/64 9/16
18 5/16 7/32 19/64 13/64 5/8
20 21/64 15/64 5/16 7/32 3/4
24 3/8 17/64 3/8 1/4 3/4

The chart makes little sense but I saved it anyway, thanks. I haven't
graduated to countersink yet, but by golly I will.