J

John R. Graham

Active Member
Over the Christmas holidays I completed a new improved "wet work" corner in my shop: stainless steel industrial sink with large side drain area, commercial restaurant-style pre-rinse faucet, FRP panels on the walls. Last weekend I was just doing a little finishing touches work, attaching a paper towel roll holder, and while drilling the holes, I hit a drywall screw, and made a discovery: man, are those made out of hard metal. In trying to drill it out, I've dulled three high speed steel bits (a tungsten coated one, a cobolt steel one recommended by Home Depot, and a brand new bit that came from Avery) and, mostly out of desperation, ruined a brand new carbide-tipped masonry bit.

Now, I am somewhat of a perfectionist, I admit, but I'm not that bad: I'm going to move the roll holder an inch to the right (a position that will still leave the unused holes covered) and drill new holes. But, I'm curious. What would I use to drill out that egregiously hard screw?

- John
 
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Assuming it's SS, the key is to use a slow turning drill with lots of lubrication (Boelube, etc). And a good bit (cobalt). Even then you will wear out the bit but you should make headway. I think I went thru 2 or 3 bits to drill 6 EFG probe holes in the SS exhaust.
 
If it's a drywall screw in drywall, don't bother with the drill. Hack out enough drywall and get a crescent wrench on it.

Spackle wil make it perfect.....:D

You can do a lot of stuff to drywall that you can't do to aircraft.....
 
The issue is that the drywall screw is behind this nice new piece of fiberglass paneling that I glued over the drywall. Taking it out is thus not an option. I was trying to avoid extra holes in the FRP.

- John
 
Drywall screws are hardened carbon steel, some have coating on them that look grey or silver. They are hardened to the point that they will break before bending any. Drilling into it would be like trying to drill a metal file, hardly practical.

Bird
 
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