Drilling out hardened steel screws question

[Martin Noakes]

Hi all

I'm about to lift an Oak floor that has shrunk in order to re-lay it after straightenin the boards.

Here's a picture one of the gaps!

to the shrinkage the screws have been bent over and I'm unable to unscrew them.

The screws are hardened steel BZP and I wondered if anyone knew which type of drill bit I would need to drill the heads off. I have a couple of metalwork drills and they don't touch the screw heads.

Or maybe another suggestions/approach for unscrewing them.

Cheers

Martin

[Tom]

They drill thru brake rotors, files etc. Not cheap, but I got a set at ww show and ended up needing it that very day to remove a frozen shock mount bolt on wifes car. You will need a small hole to get larger bit started.

[Saudade]

You need carbide drill bits (carbide tipped). You could try a bit big enough to pop the head off but some threaded length may still grip the board. I'm surprise the boards didn't split and bent the screws instead.

[John Grossbohlin]

Can you post a picture of the screws in the flooring and if possible a picture of just a screw?

John

[Martin Noakes]

Some have split!

Cheers for the advise

Mart> > Hi all

[Martin Noakes]

Not at the moment as I haven't been able to unscrew any of them.

Cheers

Martin

[John]

It's not entirely clear from the photo but what are the floorboards screwed into? Might it be possible to cut through that substrate, pull up the floorboards, and then remove the still screwed on substrate piece from the underside at your workbench?

Just a thought.

J.

Mart> Hi all

[Martin Noakes]

They're screwed in to a softwood frame which is infilled with insulation (jablite).

Cheers

Martin

[Frank K.]

More thoughts.

A cobalt bit or try a reciprocating saw with a long, fine tooth, bimetallic blade. If the bimetallic blade won't cut the screws, get a diamond blade. Just lift the board enough to get the blade under it and cut off the screws.

Frank

[Martin Noakes]

[Wilson]

[Paul Franklin]

Perhaps this would work? Take a piece of 1/4 inch hollow steel tubing. With a triangular file, file some teeth in one of the ends (you are essentially making a 1/4 diameter hole saw without the center bit). Chuck it in your drill and use it to bore down around the outside of the screw, separating the screw from the plank. (You can use a scrap with a 1/4 hole in it as a guide to get the bit started in the right place, since it will tend to wander with no center bit.) Once you have done this to all the screws, lift the plank off, and remove the screws with pliers. The 1/4 holes in the planks can be filled with wood plugs.

I've seen commercial versions of this tool for sale, but don't remember where at the moment. It'll be slow going, but beats destroying the floor to remove it.

HTH,

Paul

[Toller]

What's carbaloid?

>

[hylourgos]

I just read the same and was about to ask the same too. So ibid.

...and if it's anything like leatherette, I'll pass.

H

[hylourgos]

I take it this is not normal oak plank flooring you can get at the flooring stores (pic did not look like normal T&G boards, anyway). Floorboards are normally nailed for this very reason, among others, but there may have been a good reason to use screws here.

Regardless, I would first try to screw them all the way through. If that didn't work, a Sawzall with a long bi-metal blade would most likely eat it and ask for more. Small hole saw is the last option, because fitting many special-made plugs won't be fun.

Good luck and tell us how you do, H

[Dhakala]

FUD for "carbide"

[Sam]

Try a crowbar. Maybe the screws will pull out of the softwood sleepers. Sam

[CW]

No better than HSS. They are not titanium (which would make a lousy drill bit). They are HSS bits with a thin (.0001") titanium nitride coating.

[CW]

If regular HSS won't do it, cobalt won't either.