# removing a stripped screw (ROberston) square head



## wilsonfrench (Dec 26, 2008)

Hi. I am trying to remove a stripped screw (ROberston head - square head)...with all the furstrating turning, it is now round....
I have tried using a tool from a hardware store (an extractor)...kinda looks like a drill bit with a cone shaped head...
anyway...any ideas? thanks..
I really need to preserve the wood from which I am extracting the screw...
thanks
I have tried needlenose plyers, vise grips....


----------



## USP45 (Dec 14, 2007)

Get a good quality screw extractor. Not one of those cheap ones.


----------



## sausagefingers (Nov 16, 2008)

Yeah that's your best bet. I actually have that Grabbit thing. Half of the time it works really well, the other half it pretty much sucks. haha.


----------



## Nestor_Kelebay (Jun 17, 2008)

At this point, can you not drill off the screw head and pull the wood you want to salvage off the shank of the screw? If you know the screw shank diameter, just choose a drill bit slightly larger. The Robertson style of head will ensure that the drill bit gets started centered in the middle of the screw shank. Once you drill through the thickness of the head, the screw head should come off on the drill bit.

Also, if you're going to drill the head off, it makes some sense to get a drill bit that won't dull quickly from drilling steel. The gold colour titanium bits simply have a coating on them that's MUCH harder than high speed steel, and they are a good choice if you've only got a few screw heads to drill off. Cobalt bits are made of a steel that's harder than the High Speed Steel of regular drill bits, but not nearly as hard as the coating on titanium bits. So, once the gold coating on titanium bits wears off, you've essentially got an ordinary High Speed Steel drill bit. Cobalt bits are softer than the coating on Titanium bits, but you can cobalt bits sharpened so that after sharpening, you essentially have a new cobalt bit.

Next time, before you get to the point where the hole is round, stick a small slot screw driver into the hole DIAGONALLY, and then twist the screw out, either with the screw driver or by gripping the blade of the screw driver with vice grips.


----------



## ponch37300 (Nov 27, 2007)

Can you use the next size bigger square drive? If it is a #2 square you could try pounding a #3 square drive in, might have to pound it in to make it fit.


----------



## wilsonfrench (Dec 26, 2008)

Nestor_Kelebay said:


> At this point, can you not drill off the screw head and pull the wood you want to salvage off the shank of the screw? If you know the screw shank diameter, just choose a drill bit slightly larger. The Robertson style of head will ensure that the drill bit gets started centered in the middle of the screw shank. Once you drill through the thickness of the head, the screw head should come off on the drill bit.
> 
> Also, if you're going to drill the head off, it makes some sense to get a drill bit that won't dull quickly from drilling steel. The gold colour titanium bits simply have a coating on them that's MUCH harder than high speed steel, and they are a good choice if you've only got a few screw heads to drill off. Cobalt bits are made of a steel that's harder than the High Speed Steel of regular drill bits, but not nearly as hard as the coating on titanium bits. So, once the gold coating on titanium bits wears off, you've essentially got an ordinary High Speed Steel drill bit. Cobalt bits are softer than the coating on Titanium bits, but you can cobalt bits sharpened so that after sharpening, you essentially have a new cobalt bit.
> 
> Next time, before you get to the point where the hole is round, stick a small slot screw driver into the hole DIAGONALLY, and then twist the screw out, either with the screw driver or by gripping the blade of the screw driver with vice grips.


 
ok I got it out...thanks!...although now I have another problem...the (shank?) is still embedded int the wood...I need this screw hole...
how can I get it out? the diameter seems a little small to use that extractor thing...and I cannot drill into the centre of the shank even with a steady drill and bit...
can I vise grip twist it out (actually tried this...but cannot get leverage)....it sticks out about 1/8"....
can I "hole saw" it out? and then put a dowel in there? thanks.
see photo./


----------



## Nestor_Kelebay (Jun 17, 2008)

Is the head of that second screw OK? Can you remove it with a screw driver?

Before you use the hole saw to cut around the screws, I'd try using a small chisel (like a 1/4 inch wide chisel) to bevel the wood around the screw so that you can get a better grip on the screw shank with the vice grips. If that doesn't work, then you can always use the hole saw to cut around the screw shank. (or cut through that piece of wood on both sides of the screws to replace that entire chunk of wood.

If you use a hole saw to cut a hole around the screws, and then break up that plug of wood with a chisel or whatever, remove the screws and then plug the hole with a dowel, how are you going to ensure that the screw you put into the dowel goes into the original screw hole in the larger board behind?

Instead of using a hole saw, what do you think of the idea of cutting that 2X4 (or smaller piece of lumber) on either side of the screws, breaking up the lumber between the kerfs with a chisel so that you can remove the screws, and then installing a new piece of OAK 2X4 material where the old piece was. Use flat head screws above and below the original screw hole to hold the oak to the 2X6 behind it. That way you can put the new fastener just into the new oak, and not necessarily into the original screw hole?

Alternatively, can you replace a section of that smaller lumber on top with a piece of hardwood?

Why does the screw hole have to be in that location?


----------



## wilsonfrench (Dec 26, 2008)

Nestor_Kelebay said:


> Is the head of that second screw OK? Can you remove it with a screw driver?
> 
> Before you use the hole saw to cut around the screws, I'd try using a small chisel (like a 1/4 inch wide chisel) to bevel the wood around the screw so that you can get a better grip on the screw shank with the vice grips. If that doesn't work, then you can always use the hole saw to cut around the screw shank. (or cut through that piece of wood on both sides of the screws to replace that entire chunk of wood.
> 
> ...



all good ideas...however, am not terribly handy and it all seems over my head///
as for the screw in that location...well, the bracket to which it attaches has a pre-matched hole...I suppose I can predril another hole 1" to the left...


----------



## Nestor_Kelebay (Jun 17, 2008)

Would this work:

1. Place that bracket over the screw now, and trace out the bracket's outline on the 2X4 board.

2. Then, use the holesaw to cut into the 2X4 about 1/4 inch. Before doing that, though, remove the pilot drill bit and wrap the end of a 1/8 inch drill bit with masking tape so it fits in the pilot bit hole. That way you've got a smaller pilot drill bit so you can center the hole saw over the screw better.

3. Chip out the wood within that hole saw kerf with a small chisel (or whatever).

4. Grab onto the screw shank and twist it out with a pair of vice grips.

5. Remove the smaller screw the same way if necessary.

6. Cut a piece of dowel 1/4 inch long and glue it into your hole with white wood glue. Allow the glue to set up overnight, and then sand it down flush with the surrounding wood.

7. Place the bracket on the board so it's sitting within the outline drawn earlier and mark the hole location on the dowel with a circle.

8. Mark the center of that circle as accurately as you can by freehand.

9. Use an awl to impress a notch in the center of the mark you made in Step #8.

10. drill a small pilot hole through the dowel, and enlarge the hole once or twice with progressively larger drill bits until you're at the hole size you need for the screw you intend to install.

Another option you have here is to use something called an "undercut head screw". Undercut head screws come in a limited range of sizes, but basically they have a head on them that's two or even four nominal sizes smaller than a normal head. So, if you have a #8 undercut head screw, the head on it will be the same as you'd find on a #6 screw. Similarily, the head on a #10 reduced head screw will be the same as that on a #8 screw. In this way, you can use a larger undercut head screw to repair a stripped hole for the screws in a door hinge, say. If the #8 screws holding a door hinge are loose because the holes are stripped, you can replace them with #10 undercut head screws. The larger threads of the #10 undercut head screw will grip the wood well, and the smaller head on it will still fit the door hinge properly.

For example, take a look at these two web pages:
http://www.spaenaur.com/view_pdf.asp?Page=B99
http://www.spaenaur.com/view_pdf.asp?Page=B100

They show that Spaenaur sells #10 X 1 1/2 inch long Phillips drive oval head sheet metal screws with three different head sizes:
Stock # ST22P has a standard #10 size head
Stock # 2046 has a #6 size head, and
Stock # ST69P has a #8 size head

So, if you had a door hinge with #10 X 1 1/2 screws in it, and one or more of those screw holes were stripped, you could put in a #12 X 1 1/2 reduced head screw. In this case it would be a # ST427P with a #8 head. Alternately, you could put in a #14 X 1 1/2 screw with a #10 head, which would be an ST451P.


----------



## wilsonfrench (Dec 26, 2008)

thanks!



Nestor_Kelebay said:


> Would this work:
> 
> 1. Place that bracket over the screw now, and trace out the bracket's outline on the 2X4 board.
> 
> ...


----------



## Chemist1961 (Dec 13, 2008)

Yep Nestor but Spaenaur has minimum order even for cash when you walk in... they're just up the road from me.
Wilson, can you show us the bracket . It looks like stair rail or similar


----------

