försänkning

Försänkning is a term used in metalworking and woodworking to describe a process that creates a conical or angled recess at the entrance of a drilled hole. This recess is designed to accommodate the head of a screw or bolt, allowing it to sit flush with or below the surface of the material. This serves both aesthetic and functional purposes.

There are several ways to achieve a försänkning. In machining, this is typically done using a countersink bit, a cutting tool with a tapered end that matches the desired angle. The countersink bit is rotated and pressed into the pre-drilled hole, removing material to form the recess. In woodworking, a countersink bit is also commonly used with a drill. For simpler applications or when precision is less critical, a drill bit can be used at an angle to create a chamfered edge, or a larger drill bit can be used to partially widen the top of the hole.

The primary benefit of försänkning is to create a clean and finished appearance by hiding the fastener head. This is particularly important in visible applications where protruding screw heads would be unsightly. Functionally, it prevents snagging on the fastener head, which is useful in areas where objects might slide across the surface. It also allows for multiple layers of material to be joined without the top piece being raised by the fastener head. The angle of the försänkning typically matches the angle of the fastener's head, commonly 82 degrees or 90 degrees for screws and bolts.