Langlochbohrer

Langlochbohrer is a drill bit designed to create elongated holes, or Langlöcher, in materials such as wood, plastics, or light metals. These slots accommodate adjustable joints, allow movement, or provide alignment in furniture making and cabinetry. By producing a long, narrow opening rather than a round hole, Langlochbohrer enables components to slide or align precisely after assembly.

Typical construction and variants vary by model. Most Langlochbohrer have a relatively long cutting section with a stable shank and are offered in materials such as high-speed steel (HSS) or carbide-tipped variants for increased durability. The exact geometry, including slot width and length, depends on the intended use and the dowel or fastener size that will pass through the slot. Some designs incorporate guides or centers to help start and keep the bit straight, which helps produce clean, straight slots.

Applications and use

Langlöcher are common in cabinet making, joinery, and hardware installation where adjustment or movement is needed after assembly. The elongated slot permits lateral or longitudinal adjustment, helps compensate for wood movement, and can reduce stress concentration around fasteners. When using a Langlochbohrer, the workpiece is typically clamped and drilled with a drill press or a machine that maintains perpendicular alignment to ensure a clean slot. After drilling, the entry and exit edges are deburred or chamfered as needed.

Related tools

There are also router-based Langlochfräser (slot milling cutters) used to create similar slots with a router, offering alternatives for different work setups and slot dimensions.