Hi Guys,

How many times have you put a wood screw into something and have had the head break off ?

I started to put a new latch plate on the kitchen door recently. Unfortunately I had not chiselled out quite enough wood from behind it, so I started to remove the two wood screws that I had used and both screw heads broke off leaving the shank in the wood frame with no way of gripping them in order to get them out !

A little frustrated after spending 15 minutes or so trying to dig enough wood away to get a pair of grips on them, I gave up and decided to make a hollow drill bit and get them out that way. On the basis that I can always put a wooden plug into the hole, I set to and made this drill bit.

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I used a 70 mm long piece of 1/4" silver steel to make this drill.

I drilled it using a 4 mm drill, down the centre, then slotted it for a distance of about one inch starting 6 mm from the end with a 3 mm slot drill. After I then used a 1.5 mm slot drill to cut six teeth in the end, after which I hardened it by heating with a cooks torch until the end was cherry red then plunging into a cup of water. I then tempered the end to take the glass hardness off.

The teeth were cut by eye and are not a uniform as they could be. Setting the rod over by 20 degrees with a piece of plywood wasn't the best way either But it worked well enough.

The idea behind the slot is so that any wood lodged in the drill can be removed with a probe. In actual use a couple of digs with the drill bit allowed both the screws to be removed without too much trouble. I filled the holes that were left with dowel, glued and tapped into the wood frame.
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