Very often, a broken drill should just throw it away because of the inability to even re-ground it. However, it can be converted into a punch. It is enough to the breaking point to make the angle marked in the figure. For such an operation better suited for the drill of large diameter. This punch will make it easier to obtain holes in concrete. Slightly after each hammer blow, the punch should be slightly rotated around the axis.
L. ANDARALO, M and n s K, Belarus
Recommend to read
STOOL-TRANSFORMER
This versatile stool which if necessary can turn into a small stable ladder, absolutely necessary in those apartments where there are high cabinets and mezzanines. To produce such a...
CRUISE RADIO-UNIVERSAL
For those who have passed the first stage of learning the art of radiopilot on the simplest gliders and pondered the project of the first motor cars will probably be interesting and...
