The Difference Between Self-Tapping Screws And Self-Cutting Screws

There are many types of screws, each used in different fields. Many people cannot distinguish between Self-Tapping Fastening Nails and self-cutting screws. The following is an analysis based on their shape, material, and application.

Self-Tapping Fasteners generally refer to pointed, coarse-threaded, hardwood screws, but they can also be made of aluminum alloy or plastic.

Self-cutting screws have various head shapes, including round, flat, countersunk, and full-face.

Self-tapping screws are used for non-metallic or softer metals. They drill holes that do not require tapping. The screws used are different from regular screws; the head is pointed, and the thread pitch is relatively large, somewhat similar to a chip-free tap. They can be screwed in directly without tapping. This method is commonly used with metals and plastics.

Self-cutting screws are available in carbon steel and stainless steel, with 1022 medium carbon steel being the most common material. The material is generally carburized steel, and after heat treatment, the surface hardness is not less than 45HRC. Compared with ordinary screws, for the same major diameter, its pitch is larger, and its minor diameter is slightly smaller, which is standardized. Self-Tapping Thread-Forming Screws are commonly used in doors, windows, and sheet metal.

Auto-Tapping Screws can use their own threads to "tap, drill, squeeze, and press" the corresponding threads into the materials being fastened, making them fit tightly together.

Self-Tapping Fastening Nail, also called self-cutting screws, is a type of threaded fastener that self-drills its own internal threads into pre-drilled holes in metal or non-metal materials. Self-tapping screws are mostly used for connecting thin metal plates (steel plates, saw blades, etc.). During connection, a threaded pilot hole is first drilled in the parts to be connected, and then the self-tapping screw is screwed into the threaded pilot hole. Because the thread surface of the self-tapping screw has a high hardness (≥45HRC), it can tap internal threads in the threaded pilot hole of the parts to be connected, thus forming a connection.