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зенкер
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Flat-bottomed hole allowing a screw head to sit flush with a surface, or a tool for making such a hole.

зенкер
1
The holes can be counterbored for the heads and then plugged.
Mission Furniture: How to Make It, Part 3
2
To make the matter worse, quite a number of the wheels were found to have been counterbored about ½ in.
Scientific American Supplement, No. 623, December 10, 1887
3
Today I counterbored the four holes in the fenders that will have 3.5 machine screws inserted to act as axles for the wheels.
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