Some do and some have self-drilling points. Follow the product data for material, thickness and required hole diameter.
Thread Forming Fixings for Sheet and Components
Self Tapping Screws form or cut a mating thread as they enter compatible sheet metal, plastic or other specified components. MacBlair groups this range within screws for different materials, making it easier to match the product to the wider task. Choose point style, thread, diameter, length, head, drive and finish for the material and thickness. Self-tapping does not always mean self-drilling, so some products still require a correctly sized pilot hole.
Clamp the parts, mark the hole and drill where the product data requires it. The pilot must allow thread formation without leaving too little material or causing excessive driving torque. For the next stage, socket screws for mechanical assemblies can support a related part of the job. Drive square at controlled speed and stop when the head seats; repeated removal can weaken formed threads in thin material.
Self Tapping Screws should be used with the material, system and working conditions in mind. Check behind sheet for cables, sharp swarf and the projecting screw point. Wear eye protection when drilling metal, remove burrs and do not use an unrated screw for structural or safety-critical connections. screw caps and covers may also be useful where the task extends beyond this category.
Keep points and threads free from damage, store sizes separately and remove metal swarf that could cause corrosion or cuts. Check labels, ratings, fixings or material condition before reuse, and remove damaged items from service. drill bits for pilot holes helps complete the surrounding work without substituting one product for another. If the screw spins, the formed thread has likely stripped; use an approved repair or larger designed fixing rather than overtightening.
Self Tapping Screws FAQs
Use them only in the compatible sheet metal, plastic or component material stated for the product. Thread-forming behaviour varies by substrate.
It must pass through the fixed component and form sufficient thread without creating a hazardous projection behind the sheet.
Repeated removal can wear the formed thread, especially in thin material. Reuse only where the system allows it and the hold remains sound.
The pilot may be too small, material too hard, alignment poor or torque excessive. Stop and correct the specification or hole rather than forcing another screw.