Blade Safety

First, those black abrasive blades are dangerous – my commentary. Diamond blades are wonderfully fast, long lasting and safe if used wisely. Use no more than a 5” blade on a 4.5” angle grinder (<12,001rpm): a 7” blade on a <8001rpm grinder: a 9” blade on a body grinder (<6001rpm). The best blades have hubs/flanges so they screw onto the the grinder. Make sure the blade is firmly on the arbor of the grinder, connected by almost all the screw threads. Regularly check the tightness of the screws of the hub. Never twist the blade during the cutting process and avoid putting the blade all the way into the 12 stone; leave at least 1⁄4” space to the hub. Check for cracks regularly.