Drilling of small holes is a difficult task and has only been possible with mechanical machining for a long time. For the watch industry, a solution could be found by producing special, own mechanical tools. These tools are still not generally available today.

It has been shown that the spark erosive processing provides an excellent solution for this problem. When the machine tool manufacturer MATRA-Werke GmbH in Frankfurt presented an EDM drilling machine in 1986, the experts were astonished. At a first performance of the machine in Frankfurt, the exclamation “it drills like a devil” was made. Thus, the brand name “Bohrteufel” (drill devil) was born, which stands for EDM drilling process since then.

With this method, drill holes of 0.2 to 6.0 mm with a drilling depth of up to 600 mm can be produced in all electrically conductive materials very fast. The drilling speed into hardened tool steel (e.g. 20 mm high) with a tube electrode of 0.8 mm diameter is about 1 sec./mm. The drill tolerances are a few hundredths of a millimeter depending on the machining task. Due to the contact-free operation of the electrode on the work piece, a drill hole can also be inserted without any problems into slanted surfaces.

The choice of the electrode and the working fluid is important for a high-quality machining with the ”Bohrteufel”. The technology of the machine is precisely coordinated with the work equipment.

Until now a whole series of high-tech machines has been developed from the “Bohrteufel”, which was presented more than 20 years ago. In 2005, MADRA-EDM company took over all the rights of the “Bohrteufel”-series and the machines have been subject to constant enhancement since then.

In addition to the machine series of the BT-type in manual or CNC-version, also special requests of the users are fulfilled. The machines are used wherever small holes with a large drilling depth are required into high tensile and/or tough materials, e.g. carbide, titanium, non-ferrous metals, graphite, etc. The fields of application are generally tool making, for start hole drilling for wire erosion or also for bleeder holes.

The machines are also used for production tasks in aerospace, medical technology, electrical engineering, automotive production and for cutting tools. Due to continuous technological development and adaptation to special machining tasks, the application areas are constantly expanding.

Visit us in our demonstration center in Kahl or on www.madra-edm.de.