Thread: Unusual drill failure.

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Hello again.
This caught me by surprise. I was rotating my drill index to select a 3/16" drill and a 14mm jobber that was lurking with the others did a suicide jump to the floor. Followed by a loud ping. The total drop being about 1mtr. In the first pic you just get the impact damage to the outer corner on the lip. Pic 2 has a small discoloured section on both pieces. The third pic I tried for a better angle. If the break had happened during use I could understand fully. Failure started at the end of a flat ground on the land behind the margin where the flute runs out into the body.
During my working life I have tortured drills to death but never seen a tool shatter from a low drop.
Regards to all.
BC

I'd say there's a good chance the bit probably had developed a crack in it beforehand and the drop just finished it off.
Sometimes all that is needed is a nick out of a flute for it to break.