Sheet Metal Screws, also referred to as Self-Tapping Screws, are fasteners with a fully threaded shank, sharp coarsely spaced threads and a sharp pointed (gimlet) tip that allows them to cut into thin gage metal, wood, plastics, fiberglass, composites and other suitable materials.
Sheet metal screws can pierce, thread into and fasten many softer materials without pre-drilling, but for use in materials such as sheet metal and hard woods a correctly sized pilot hole should be pre-drilled before these screws can be used successfully. When used in thin gage metals with a pre-drilled pilot hole a self-tapping screw is capable of cutting it’s own threads into the hole for securely fastening two metal items together, fastening wood to metal or metal to another suitable substrate material.
Our 18-8 Stainless Steel Sheet Metal Screws are available in head styles such as Hex, Pan, Truss, Countersunk Flat or Oval Heads. 18-8 Stainless Steel material provides effective corrosion protection in wet, humid environments, when used in exterior applications, and when exposed to many common chemicals. They may occasionally be slightly magnetic. Sheet Metal Screws are also available in Type 316 Stainless Steel which is recommended for use in salt water marine environments and under exposure to chlorides.
Flat Head Sheet Metal Screws feature an 82° Countersink style flat head that will fit flush with the surface when fully installed. The length of a Flat Head sheet metal screw is measured overall from the top edge of the screw head. A rule of thumb for determining correct pilot hole size for a screw is to drill a hole in the size range of it’s minor diameters, (see Tech Specs below). We have included a suggested Pilot Hole size for metal in our Technical Specifications section on this page. When necessary, a test installation may be required to confirm the correct pilot hole size for fastening into different thicknesses and types of materials.