Drilling and tapping are two distinct actions. Drilling refers to creating a smooth hole in a material with a drill bit and a pistol or bench drill. Tapping is the action that creates a thread into the side of the hole.
There are numerous kinds of taps:
- Bottoming taps are used to cut a thread to the bottom of a blind hole.
- Taper taps are used to gradually thread a hole in a material that is difficult to cut or prone to breaking.
- Plug taps are used in holes that go through the material and where there is room at the bottom of a blind hole.
- Hand taps have straight flutes and are for general purpose projects with both blind and through holes.
- Spiral flutes are used in blind holes when the threads need to be close to the bottom of the hole and are good at moving material out of the hole. There are numerous helix options, and the degree of the spiral needed for a project often depends on the type of material.
Please See our Handy Drilling & Tapping Chart for Metric, Metric Fine & Imperial threads.