How To Tap Holes - Tips

[GBWM]

My taps always break below the surface.

Same as mine. This one was quite lucky.

Some additional hints:
1. See that the drilling is rectangular to the surface
2. Countersink before tapping: lightly on the back and to the tap diameter on the front
3. Take special care that the tap is rectangular to the surface. Assess the right angle from 2 sides against a visually clean backdrop or use a tapping guide.

You're absolutely right. I'm always countersinking the holes if its posible. Also I'm considering to make "tapping guides" - could be handy.