Ameeji Hardwares Suppliers

Self-drilling screws showing flute. A self-tapping screw is a screw that can tap its own hole as it is driven into the material.

is a screw that can tap its own hole as it is driven into it. For hard substrates such as metal or hard plastics, the self-tapping ability is often created by cutting a gap in the continuity of the thread on the screw, generating a flute and cutting edge similar to those on a tap. Thus, whereas a regular machine screw cannot tap its own hole in a metal substrate, a self-tapping one can (within reasonable limits of substrate hardness and depth). For softer substrates such as wood or soft plastics, the self-tapping ability can come simply from a tip that tapers to a gimlet point (in which no flute is needed). Like the tip of a nail or gimlet, such a point forms the hole by displacement of the surrounding material rather than any chip-forming drilling/cutting/evacuating action.
Some self-tapping screws are also self-drilling, which means that, in addition to the tap-like flute in the leading threads, there is also a preliminary drill-like fluted tip that looks much like the tip of a center drill. These screws combine a thrilling-like action and the fastener installation itself into only one driving motion (instead of separate drilling, tapping, and installing motions); they are thus very efficient in a variety of hard-substrate applications, from assembly lines to roofing. 
We stock a wide selection of Roofing Screws in a Zinc or Silver Ruspert that meet all recognised industry standards. For use with a variety of applications.

A self-tapping screw is a screw that can tap its own hole as it is driven into it. For hard substrates such as metal or hard plastics, the self-tapping ability is often created by cutting a gap in the continuity of the thread on the screw, generating a flute and cutting edge similar to those on a tap. Thus, whereas a regular machine screw cannot tap its own hole in a metal substrate, a self-tapping one can (within reasonable limits of substrate hardness and depth). For softer substrates such as wood or soft plastics, the self-tapping ability can come simply from a tip that tapers to a gimlet point (in which no flute is needed). Like the tip of a nail or gimlet, such a point forms the hole by displacement of the surrounding material rather than any chip-forming drilling/cutting/evacuating action.

Some self-tapping screws are also self-drilling, which means that, in addition to the tap-like flute in the leading threads, there is also a preliminary drill-like fluted tip that looks much like the tip of a center drill. These screws combine a thrilling-like action and the fastener installation itself into only one driving motion (instead of separate drilling, tapping, and installing motions); they are thus very efficient in a variety of hard-substrate applications, from assembly lines to roofing.

Hp self drilling screw quality product in house manufacturing