Self-Tapping vs Self-Drilling vs Self-Piercing Screws

Last Updated on January 12, 2023 by Marsh Fasteners

Not all screws are made the equal. Different sizes, threads, metals and grades are complimented sophisticated designs that create enhance action - ideal for hard metal substrates and plastics that would otherwise need a hole cut in them first to take the screw.

Manufactured with a variety of thread-cuts and heads, depending on what they are needed for, they are far more efficient than ordinary screws for precision fastening with substrates that might otherwise break a drill bit or crack in the drilling process.

Self-Tapping Screws

The baseline capability of the self-tapping screw is its enhanced penetrating capability, thanks to the ‘tapping’ action created by cuts in the screw threads to create a ‘twin-lead’ thread. Many self-tapping screws are also self-drilling, and apart from blunt-edged self-drilling screws used for closely fitted substrates, all self-tapping screws have sharp points to help them penetrate the metal or plastic.

Self-drilling screws

Self-drilling screws have an additional flute in the leading threads in addition to the cut, so while they are also self-tapping, they flute at the tip that provides a drill action to combine with the tap action. This increases the efficiency of the screw and its ability to penetrate harder substrates than those for which an ordinary self-tapping screw would be suitable.

Some self-drilling screws have blunt tips – ideal for when they need to be put through a substrate that positioned very close to another one, without damaging the neighbouring substrate.

Self-piercing screws

Also called ‘ZIP’ screws, needlepoint screws, speed, ‘saber’ or twin-fast screws, self-piercing screws have extra sharp tips that can penetrate even the thickest sheet metal. Designed for fastening the hardest substances and the most precise applications, stainless steel Zip screws come in with a huge variety of lengths and thicknesses to meet the needs of any industry.

Get in touch with us at Marsh Fasteners. As a leading stainless steel fastener specialist and partnered with manufacturers and suppliers of the full range self-tapping screws and the highest grade stainless steel self-piercing screws, we can make choosing the right fasteners easy.