[. . . ] To avoid machine self-starting, always trigger-off the switch should power supply become interrupted or plug accidentally withdrawn from the socket while motor is still running. In hand held drilling operations, only use the machine with the auxiliary handle fixed. If the selector is on " OO "position, the speed can vary up to 2000 min-1 and this speed is recommended for diameter up to 80 mm. : - always check the drill bit manufactures recommendation for use - gear shifting only when the machine is stopped and clockwise ! [. . . ] Before all works at the machine, make sure that the plug is off the mains socket. Due to its design, the machine needs a minimum of care and maintenance. Nevertheless you should always observe the following: Keep the electric tool clean. If the machine is defect let carry out a repair only through an authorized service workshop. 2 Dry Drilling Only perform dry core-drilling on brickwork and soft lime or soft sand stones. employ suitable type of vacuum and which also have ample of suction power. Plentiful suction air offers additional benefit of cooling the core drill's body and free of dust, running more freely. Moving core drill slightly back every now and then during coring process will make dust extraction more effective. In doing so make sure not to tilt the core drill bit, as this will substantially shorten its useful life. Use solid pilot inserted into the core-bit until a starting groove about 5mm deep is cut. Then remove pilot bit, otherwise it will start overheating and become unnecessarily defective. Alternatively you can also use separate hammer drilling machine to make a pilot hole which then renders removal of the pilot from core bit unnecessary. There has to be enough water to flush all the residue out of the groove. If using pressurised water container, make sure it will deliver the required amount. starter hole guides and drill rigs assist accurate starts and guidance. If neither starter hole guide nor drilling rig are available, use wooden template to ensure drilling starts in the proper place. When using drilling rig, make sure that: drilling machine is mounted securely; the feed control is engaged and that drill does not move by its own weight; the stand is mounted securely. For safety, the drill stand should be secured in one of the following ways: with bolt anchor, washer and quick fastening bolt (use anchor for at least 50mm setting depth). [. . . ] Re-dress more often by cutting into piece of corundum grinding wheel to reexpose diamond particles. There is proportionate relationship between hardness of diamonds impregnated segment material, cutting speed and abrasiveness of material being cut. Should core-bit jam or there is no progress made when drilling, check to ensure that there is sufficient amount of diamonds present in the surface of segments. Safety Switch Check RCD (Residual Current Device) daily, following enclosed instructions. [. . . ]