Do any of you have any rules of thumb for how big pilot holes should be for screws? I have run into a couple of situations where my guess was apparently too small.

The first was when I was trying to attach some brass hinges to a small box. The box is made out of white oak (very hard stuff). I got the screw in about 1/2 way and it broke. I made the next pilot hole a little larger and got about 3/4 of the way in before the screw broke.

I blamed the screws that came with the hinges as being of poor quality and have not bought replacements yet.

Then yesterday I was putting some 1 inch screws through a piece of the same white oak which I used for a fence on my cut-off sled. I managed to snap one of those large screws in half.

After some trial and error with a scrap of the oak I figured out which size works.

But in the future I would like to avoid breaking screws inside of my workpieces.

Any hints?

Thanks,

Jeff Skory