Screw snapped below wood surface

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knights
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Screw snapped below wood surface

Post by knights » Sun Oct 21, 2018 7:28 pm

Hi

I was replacing a new hinge on an oak frame and the screw head snapped below the surface. I am unable to grip the screw as it is below the wood surface. What is the best way to extract the screw for it to be replaced?

Many thanks

Ray
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big-all
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Re: Screw snapped below wood surface

Post by big-all » Sun Oct 21, 2018 7:35 pm

you need brass or stainless steel furniture on oak
where they slotted screws??
if so the are tapered so maybe soldering iron to reduce the bond
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Re: Screw snapped below wood surface

Post by knights » Sun Oct 21, 2018 7:39 pm

It was carlisle brass hinges and screws. Hinges seem good but the screws seem rubbish. What do you mean soldering iron?
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Re: Screw snapped below wood surface

Post by big-all » Sun Oct 21, 2018 7:44 pm

on the broken end so the heat starts to break the bond
assuming they are number 7 wire gauge then maybe a 6mm plug cutter and a large say 10mm dowel to plug
random link
https://www.amazon.co.uk/SODIAL-Cutter- ... B0144101NQ
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Re: Screw snapped below wood surface

Post by Dave54 » Sun Oct 21, 2018 7:45 pm

I've usually managed to get them out by chiselling down a bit to expose a stub, and then using a small pair of Mole grips or similar.
For the future, run a steel screw the same size into a pilot hole first. Candle wax on the threads helps stop them sticking.
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Re: Screw snapped below wood surface

Post by Job and Knock » Sun Oct 21, 2018 9:12 pm

Brass is pretty soft and shouldn't be screwed with a power driver unless you have an adjustable model and even then impact drivers will tend to bottom out the screw in the countersink and snap it off, so the last bit needs to be hand screwed. Stainless steel is a little harder, but still subject to spelching and heads snapping when over driven, just like brass. This is even more the case when screwing into dense or hard woods such as oak, mahogany, walnut, etc. Another thing is that pilot hole sizes for hardwoods are also a little larger than for the same screws into softwoods. TBH these simple facts seem to pass many joiners by, judging from the dozens and dozens of stainless steel screws I need to replace (mainly on hinges) on every project I work on these days. Ex-house bashers familiar with working on price are the worst offenders in terms of mashing or breaking off heads in my experience
Dave54 wrote:I've usually managed to get them out by chiselling down a bit to expose a stub, and then using a small pair of Mole grips or similar.
Likewise. Radio pliers are also good. The hole then needs to be redrilled with a brad point bit and a hardwood dowel glued in and trimmed-off flush before piloting again
Dave54 wrote:For the future, run a steel screw the same size into a pilot hole first. Candle wax on the threads helps stop them sticking.
For stainless steel screws and brass screws alike I pretty much always pilot drill then mount the ironmongery with identical size (but if possible slightly shorter) steel screws. Once it's all fixed the steel screws are backed-out one at a time and replaced with stainless steel screws or brass screws as appropriate. With slotted this gives me the chance to align the screw slots horizontally if there is the time (which looks a lot better on the posh jobs). Brass screws I often drive the whole way in with a hand screwdriver (especially for sizes #6 or 3.0mm and smaller - larger sizes are less of an issue), stainless steel are driven 3/4 of the way preferably with a cordless drill or screwdriver (NOT and impact driver) and finished with a hand screwdriver. High speed and mashed heads go hand in hand so I have a selection of old-fashioned screwdrivers and ratchet drivers to do this stuff - but unlike the fast and dirty brigade who think it can all be done with an impact driver, I may take a little longer but I don't banjax screw heads (always a "pull" on high class work)
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Re: Screw snapped below wood surface

Post by big-all » Sun Oct 21, 2018 9:13 pm

as an aside
if you are using new hinges the screwholes may be almost clear off the old screw positions
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Re: Screw snapped below wood surface

Post by big-all » Sun Oct 21, 2018 9:43 pm

another choice
is dremill size size grinding disk cut a 3-5mm deep slot
now the disc will hate the wood so will tend to grip and throw when in the wood so careful progress so the machine dosn't pivot and flex and break the disc
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Re: Screw snapped below wood surface

Post by Grendel » Mon Oct 22, 2018 5:52 pm

Job and Knock wrote: For stainless steel screws and brass screws alike I pretty much always pilot drill then mount the ironmongery with identical size (but if possible slightly shorter) steel screws. Once it's all fixed the steel screws are backed-out one at a time and replaced with stainless steel screws or brass screws as appropriate. With slotted this gives me the chance to align the screw slots horizontally if there is the time (which looks a lot better on the posh jobs).
I tend to find a pair of electrians cutters do it for me , they are harder than the brass and will dig in to allow for turning .
Like you I often run a steel screw in first and on cheapo flush doors piloting is practically essential as I've seen the timbers split quite easily by just driving the screws in.
On the dressing of slots that was something I was taught early on in my career . However , some time later we were asked not to do it , this being on period properties , as the lining up of slots means some screws are over torqued and some are under torqued and indeed dressing doesn't seem to have been anywhere near as common in the past. Personally I can see the argument although I tend to think it was probably an issue with the coarser threads of old screws but much less an issue nowadays.
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Re: Screw snapped below wood surface

Post by Dave54 » Mon Oct 22, 2018 6:24 pm

I bought a pair of these earlier on in the year. haven't used them yet, but they look good quality.
https://www.amazon.co.uk/Multi-function ... B002L6HJAA
I nearly always used to "dress the screws" Never had a problem with it, and it looks better.
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Re: Screw snapped below wood surface

Post by Grendel » Tue Oct 23, 2018 7:16 am

Can't disagree on the aesthetics of all the slots lining up. I have on occasion been asked to dress pozi screws so that they all in a + position . That seems to be much less done and I always think replacing with slots would look better anyway.
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