Product Details However, using this drill bit in a bench drill, rather than a pendant motor or flex shaft, will reduce the risk of of breakage when drilling glass or stone. The drill bit should be used intermittently with light pressure rather than a single, high pressure action. Using cooling liquid such as drilling oil or water will improve tool life and attract any dust. Whilst using a cooling liquid we also recommend that you take note of drill speed suggested on packaging. Also we advise dipping the burr into water at regular intervals to keep the surface of the material wet and cool. Special care must be taken when using water with electrical tools.
