Both self tapping screws and drill tail screws have threaded bodies and can self tap, but they are still different, with the following differences:
1. Appearance differences
The lower part of the thread of the drill tail screw comes with a flat end, similar to a drill bit, which is professionally called a milling tail. The thread of the self tapping screw does not have a drill tail and is a smooth thread.
2. Different uses
Self tapping screws are used on materials with low hardness, such as non-metallic or softer metals (such as color steel plates). They can drill, squeeze, press, and tap the fixed body into corresponding threads on the fixed material using their own threads, making them closely fit each other. Drilled tail screws are mainly used on light steel structures and can drill through thin steel plates. They are more widely used in steel structure factories and other buildings than self tapping screws.
3. Usage differences
Self tapping screws often have a pointed end and no drill tail at the end. Before entering, it is necessary to use an electric drill or pistol drill to make a prefabricated hole on the object, and then the self tapping screw can be inserted. The drill tail screw, due to its own drill tail, does not require pre drilled holes when screwing in steel plates, wood, etc. The drill tail at the tail of the screw is equivalent to a drill bit, and drilling and screw insertion are completed synchronously.