How to choose a right self drilling screw for use?

Key Design Features to Consider when Selecting a Suitable Self-Drilling Screws

Drill Flute

The length of the drill flute determines the metal thickness that can be drilled. Drill flutes allow the drilled material to exit the hole. If the drill flute becomes completely embedded in the material, the drill chips will clog the flute and cause the cutting action to cease. If this occurs, the heat from the drill chips could cause the drill point to become over-heated and fail.

Point Length

The drill point is the unthreaded section from the drill point to the first thread. This length must be long enough to completely drill through the material before the threads engage. If the threads engage too early, they can cause the fastener to bend and break.

Screw Wings

It is necessary to use screws with wings when fastening wood, over ½” thick, to metal. The wings will ream a clearance hole and keep the threads from engaging too early. If the threads engage too early, this could cause a separation of the fastened material from the base material (jacking). Once the wings hit the metal material, they will break off, allowing the threads to engage.