Select Self-Drilling Screws by Drill Point Length

The drill point length determines which metal thickness a self-drilling screw can penetrate, and wrong selection leads to failed drilling, thread stripping or loose connections.

Short-drill point screws (such as #2/#3 points) fit thin metal sheets below 3 mm. They are widely used for thin-gauge metal roofing, light weight wall panels and common indoor metal frame installation. They drill fast for thin substrates and avoid over-penetration.

Longer drill-point screws like #5 points are designed for thick steel plates and sandwich panels. In factory building enclosure, cold-storage and large steel-structure projects, they fully drill through thick base steel and insulation composite panels to achieve stable fastening.

Several practical points deserve attention. First, match drill-point length to total substrate thickness, making sure the point can fully pierce all layers before threads engage. Second, keep vertical driving angle; tilting will break the drill tip. Third, control electric-tool torque. Excessive torque deforms panels; insufficient torque causes poor sealing. Besides, choose proper anti corrosion coating for outdoor or coastal working conditions.

Reasonable drill-point selection improves installation efficiency and guarantees long-term connection reliability for metal construction projects.