Shopsmith Forums

Hi, anyone have any idea what these are? I first thought they were some sort of wood screw depth gauge, or countersink, but they are not sharp at all. Then I started thinking maybe they were key blanks, or lock picks. I can't find anything resembling them on Google.

Thanks for looking, Seasons Greetings.
Mike -

They look like old countersink drill bits.

Yep!

garys wrote: ↑Fri Dec 17, 2021 10:14 pm They look like old countersink drill bits.

Thanks for the replies. Well that was one of my guesses. Upon closer inspection I think I can see a slight rake on the side cutting edges. Very dull, must have been used a lot.

Have a great Christmas,
Thanks again, Mike -

Sure look like countersink bits. Long ago Dad had a similar thing he called a 'gimlet'. Simple boring tools, the one in Dad's tool box resembled the bottom one in the photo and I think was a rudimentary
step drill.

Yes, I am thinking these must be the modern version.
Thanks, Mike

Sorta. They do not have the shank clearance portion.

They're for drilling countersunk holes for wood screws. The number on them is the screw size number (10-12, 8-9, etc.) and the other number is the screw length. I have a few old similar ones lying around. The ones in your "modern version" are much better.

The old kind work surprising well in my experience. As JPG points out, the newer ones lack shank clearance and have a uniform taper.

I have a Craftsman set of these. They worked well for me.