This work comprises investigations on bone drills made of stainless steel in uncoated and thin film coated conditions. The coatings consisted of an amorphous diamond like carbon or (Nb)TiN-layer and were produced by means of plasma-CVD or PVD-procedures respectively. Rotating beam tests were carried out and it appeared, that all coated drills have slightly to clearly lower fatigue resistance compared to the uncoated reference. This can be related to the thermal influence of the coating procedure, or the modified surface characteristics. The coatings bond strength to the substrate, as well as the layer integrity were analyzed subsequently with scanning electron microscopy. Further, the cutting characteristics were compared under extreme conditions. Most of the coated drills showed equally good feed speeds like the uncoated drills. The temperature increase during drilling in animal bone was also measured but no significant reduction of bone heating could be found with coated drills.