What are the Self-Tapping screws?

A self-tapping screw is a threaded fastener that taps and drills a mating female thread in a pre-drilled hole of a metal or non-metal material. Self-tapping screws do not require a nut with a female thread, and the female thread is drilled into the material while screwing in. Commonly used in construction, decoration, roofing, glass, and other fields, drill tail screws are also known as window screws and roof screws.

Self-tapping screws need a certain external force, such as squeezing hard, to drive the screw into the material.

The following materials are more suitable for use:

Plastic, Wood, etc.

Tapping Screw Thread Types:

Tapping screws are a type of fastener that can create threads in the materials they are being driven into. There are several different thread types for tapping screws, including:

Type A Thread: This thread type is designed for use in thin materials such as sheet metal. It has a sharp point and a thread angle of 29 degrees, making it easy to drive into the material and creating a tight seal.

Type B Thread: This thread type is also designed for use in thin materials, but has a larger root diameter than Type A. It has a thread angle of 23 degrees, making it ideal for creating a stronger grip on the material.

Type AB Thread: This thread type is a combination of Type A and Type B threads, and is designed for use in materials that are thicker than sheet metal but not as thick as wood. It has a sharp point and a thread angle of 20 degrees, making it easy to drive into the material and create a strong grip.

Type C Thread: This thread type is designed for use in materials such as wood and plastics. It has a blunt point and a thread angle of 14 degrees, making it easier to drive into the material without splitting it.

In summary, the different types of tapping screw threads are designed for specific materials and applications, with different thread angles and point styles to create the best grip and seal possible.

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What are the Self-Driling Screws?

A self-drilling screw is a screw with a drilling head at the front end of the screw.

Self-Drilling Screws include the function of Self-Tapping Screws, the only difference is: no need to drill holes in advance.

The Self-Drilling Screws do not need to be too hard, because it has unique sharper bits

that can be drilled, but it should be noted that it cannot be drilled multiple times because it will cause it to loosen or slip.

Self-drilling screws can be used on tougher materials because of their sharper bits

The following materials are more suitable for use:

Color steel plate, iron sheet, tougher materials, etc. 

Self-Drilling screws can greatly reduce operating procedures and are often used in construction and decoration.

In summary, Self-drilling screws are actually a kind of self-tapping screws, but because self-drilling screws are special, everyone will distinguish them in actual use.