Keep snapping tiny Pin-vice bits!!!

Are you using them in a motortool, if so I would recommend to switch to a pinvise.

Knock on wood so fra I have only snapped one bit and that was a 0.1mm one.

Enzo:

You aren't the only person with that problem. You don't say what material you are drilling or whether the drill is hand held or in a press. Here are my general tips.

Use a center punch to create a purchase for the bit.
Use a reasonable speed, one which won't heat the material excessively.
Use some lubrication, wet water on plastic, oil on metal.
Have as little of the drill shank exposed as possible, you are breaking bits because you are flexing them, they don't like that.
Drill as close to 90 degrees to the material as you can manage.
Use only as much down-force as will cut the material.
Drill in stages. Cut a bit, clear the chips, cut a bit more, clear the chips, etc.

Good Luck

Randy

Yep. It's a pin vise. I purposely snap off the rear part of the bit to make the bit shorter. I'm doing model cars and Motorcycles. Drilling out the cross-bores in the brake rotors. Just about the only thing I haven't done was lubing and drilling in stages. Will try those and report back the results. Later.

You could check if your bits are made of I don't know the exact name but in France we call them "forets au carbure" that might translate on "something-carbide"; these bits work perfectly with machines but generally break if you use them "at hand" because they don't flex at all and are more like glass; you had rather use HSS (high speed steel) bits.

Looks like Randy has it taken care of....
I agree with Torio on the bit type...Carbides are very brittle and HSS or cobalt are better overall....

Regards, Dan