SELF TAPPING, SELF DRILLING, THREAD CUTTING
Explaining the Confusion !!
Self Tapping, Self Drilling, Thread Cutting …. So what is what ???
Self Tapping Screws work in most materials, but often can require a pilot hole. There are 3 different types of thread and point patterns.
|Type A: Found on Sheet Metal (Tapping) Screws
Type A tapping screws have coarse threads and gimlet points. They are used in thin metal, resinous plywood, and various composite boards.
Type AB: Found on Sheet Metal (Tapping) Screws
Type B: Found on Sheet Metal (Tapping) Screws
Type B tapping screws have spaced threads and a blunt point with incomplete entering threads. They are used in thin metal, nonferrous castings, resinous plywood, plastics, and various composite boards.
Self Drilling Screws (AKA Tek Screws) are for metal only and do not work well in wood because the hole that they drill in the wood is too large and the screw loses much of its initial holding power.
Thread Cutting Screws like self tapping screws have a variety of points. They work best in thicker materials as they cut their own threads similar to a Tap.