For the resonance test, let the wheel hang from a piece of string and tap lightly with a screwdriver handle or similar (no metal!). If the sound is not clear, but rather dull and hollow the wheel is likely to be damaged and should not be used. The grinding wheel should slide onto the arbor easily. Forcing it on the arbor, e.g. by striking with a hammer, may break the wheel and is not permissible for safety reasons. For the same reason the drilling out of too small an arbor bore is not permitted

Risk of electric shock if operated with a damaged power cablel - Wear suitable apparel with snug fitting sleeves. - Store grinding wheels in a dry place at a steady temperature if possible. - Never use damaged or malformed grinding wheels. - Mount grinding wheels only with the flanges supplied with the machine. The liners between flange and wheel must be of elastic material such as rubber, soft cardboard etc. - Do not attempt to enlarge the arbor bore of a grinding wheel. - Always pull out

To do this, hold a collecting basin beneath the water container. Pull out the rubber stopper (black arrow in Fig. 5) on the bottom of the water container and drain the water. Once the water has run out, put the rubber stopper back in the discharge opening. Fig.6). Note: It may be necessary to remove the screws completely in order to remove the water container. Pull the container out from below. The dry/wet grinding machine can be used for coarse or fine grinding. Please make sure that this ma