I had a customer that was installing some cabinets and trying to screw the two frames
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together. He didn’t have much luck, as the first time he attempted this he
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twisted the screw head right off of the screw. Luckily he was able to
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wrench it out. The next time, he almost got the screw all the way in, but
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heard a loud crack. He reversed the screw and noticed that the wood had
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cracked.
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It sounded like he may have not pre-drilled the holes, and that possibly he was not using the right screws.
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When you screw together two pieces of hardwood, you need to predrill the
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hole. This allows the shaft of the screw to enter the hole without
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splitting the surrounding wood, and allows the threads to cut into the
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sides of the hole. Soft wood will compress but hardwood won’t; it splits.
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The diameter of the hole you drill depends on the size of the screw. I
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usually hold up the screw and look at the shaft (the diameter excluding
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the threads). I will then find a drill bit that is the same diameter or
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slightly less before I drill the hole.
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Before you predrill, clamp the pieces together and make sure the bit is
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sharp. The spiraling action of the drill bit should remove the wood
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shavings as the bit cuts, but you should pull the bit out of the hole
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regularly to clear it. You will find that with hardwood especially, the
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shavings will compact and friction will cause it to smoke.
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The other possible problem is your choice of screws. For cabinets, you
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should be using wood cabinet screws. The manufacturer may have supplied
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you with the proper screws or at least listed the proper kind. Bore the
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screw into the predrilled hole until snug.
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