Self-tapping screws, sometimes called self-drilling screws, are a type of fastener designed to create their own threads as they are driven into a material rather than relying on pre-existing threads like those in nuts or threaded holes. A self-tapping screw features a sharp, pointed tip for cutting or forming threads in the material–eliminating the tapping or pre-drilling holes in many cases. These screws can be used with various materials, including metal, plastic, wood, and composite. Self-tapping metal screws come in multiple sizes and lengths to accommodate different materials and thicknesses. In addition, these tapping screws are available in various materials, like steel, stainless steel, aluminium, etc., with different head and drive types.
Self-Tapping Screw Head Types
Self-tapping screws come in various head styles, including flat, pan, round, hex, and more. The choice of head type depends on the specific application and aesthetic requirements.
Self-Tapping Screw Drive Types
Common drive types for self-tapping screws include Phillips, slotted, Torx (star), and hex. The drive type determines the type of screwdriver or bit needed for installation.
Two Popular Types of Self-Tapping Screws
Self-tapping screws are classified into two main types, such as:
- Thread-Forming Screws – These screws feature a flat nose with a thread pattern–creating threads during insertion. However, these screws require drilling a pilot hole before screwing, making them useful for scenarios where a secure and tight connection is needed. Thread-forming screws provide a solid grip and tighten materials securely.
- Thread-Tapping Screws – Unlike thread-forming screws, thread-tapping screws feature a sharp nose, creating their threads, and do not require drilling a pilot hole. They are widely used for assembling and disassembling applications that require frequent insertion and easy removal, such as furniture assembly.
Self-Tapping Screw vs. Self-Drilling Screws: The Difference
The primary difference between self-tapping and self-drilling screws lies in their intended purpose and tip design. Self-tapping screws feature a sharp, pointed tip that creates threads in softer materials while self-drilling screws come equipped with a drill-like tip that can bore their holes and fasten in harder materials without the need for pre-drilled holes.
Typical Applications of Self-Tapping Screws
Self-tapping screws are commonly used in a wide range of applications, including woodworking, metalworking, automotive assembly, electronics, and construction. They are used for various tasks, such as:
- Assembling Furniture
- Attaching Metal Roofing
- Securing Electrical Components
- Fastening Automotive Parts
- Installing Drywall.
