Puzzdre, I guess the guilty one of your "accident" was the vice.
Think of it: When you handholded the piece, any unwanted sideload applied to the tap simply tilts the part because of the soft holding. With the part firmly attached to the vice all sideloads are flexing the tap.
Even if you buy the most expensive Taps the situation is the same, it could be harder, but still brittle.
|