In CNC machines, solid carbide (HM) drills are generally the first choice. HSS(Co) is only used if there are specific circumstances that make a solid carbide drill unsuitable. As more and more machines are equipped with high-pressure cooling through the spindle, the use of solid carbide drills with cooling channels has greatly increased.

Dormer’s Force X drill features a reinforced cutting edge design with possible drilling depths of 3xD, 5xD and 8xD and is a versatile solution in many materials.

The Dormer Force M drill is specifically designed for stainless steels (ISO M) and titanium alloys (ISO S).

A drill with a reduced shank diameter (also called a drill with a cylindrical shank) is often used in a drill with a smaller clamping capacity, such as a hand drill or a cordless drill.

Dormer's range includes the A170 with a shaft diameter of ½” or 12.7mm. The Dormer A170 fits in a drill chuck with a maximum diameter of 13mm.

When manufacturing an internal thread, it is important to pre-machine the hole to the correct size. This is often done by means of a twist drill. For taps and thread mills, the required hole diameter is the same. If the hole is too small, there is a risk of damage to the tap or thread mill. But if the hole is too large, the screw thread will not meet the standard dimensions. Hence the importance of a good choice of this pre-drill diameter.

For metric (M) and metric fine threads (MF) there is an easy rule of thumb. Namely, the nominal size of the screw thread must be reduced with the pitch. With an M6 thread that has a pitch of 1 mm, the pre-drill diameter will be 6-1=5 mm