Self Tapping Screws - Slotted Countersunk

Self tapping screws, usually referred to as self tappers, are screws for use when fastening to metal or plastic. The main differentiator of self-tappers is that they eliminate the need for pre-drilling a hole as a separate operation.

All that is required to insert a self tapper is a pilot or punched hole to introduce the screw. They then form their own thread as the screw is driven into position. Once inserted, self tapping screws may be removed and re-used.

A slotted head on a fastener is a traditional design that is still commonly used on machine screws but now less popular on woodscrews. The biggest benefit of a slotted drive lies in its simplicity – a slotted screw has a straight slot that has been machined across the whole diameter of the head.

A countersunk head is usually used when no part of the fastener head is required to be protruding above the level of the substrate. Countersunk heads can also be recessed and filled over if a hidden fixing is required. Usually abbreviated to CSK.

We stock two different point options for self tapping screws, these are classified as Type AB and Type B.

Type AB has a sharp point on the end (sometimes called a gimlet point) and is commonly used with brittle materials and thin sheet metals. Type AB is the most common type of self tapper for general use.

Type B self tappers are flat and blunt on the end and are commonly used with light and heavy sheet metals (.050 to .200 thick), plastics, plywood, and other similar materials. They are also safer to use where the presence of a sharp point is not advisable, i.e. where manual labour is used in large scale factory processing.

Our self tapping screws are available in countersunk, pan head, flange head pozidrive options. Hex heads are also available. A selection of screwdriver slotted drive self tappers are also available with countersunk or pan heads.

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