What is a Die Grinder?

A die grinder is a tool used to polish and buff the inside of cylindrical objects. A cylindrically shaped sanding attachment, called a grinding nose, attaches to the bottom of the die grinder in a similar fashion as a drill bit goes into a drill. When metal piping is cut, small metal spurs often result where the cut has been made. These spurs can wreak havoc on connections. A die grinder is used to grind the spurs away, making the area smooth and allowing for proper installation.

A die grinder can range in size from a small handheld die grinder to bench top models. When choosing a die grinder, it is important to consider its primary purpose, what attachments must be used, and the amount of time that will be spent grinding down materials. An incorrectly used die grinder can wear out quickly and cause injury to the operator.

All die grinders have rotations per minute (RPM) ratings and no-load speeds. RPM measures how often the die grinder spins while in use. No-load speeds refer to the rotations of the tool’s spindle when it is idling. If the RPM rating is higher than the no-load speed, the die grinder could shatter upon use. It is essential to pay close attention to these ratings when purchasing a die grinder.

The RPM rating of the die grinder is the deciding factor in the tool’s usage. A die grinder with a lower RPM is best used for fine grinding and finishing work. Speeds lower than 10,000 RPM are best for this function. A die grinder with an RPM between 10,000 and 20,000 is great for creating rough finishes and minor buffing jobs. If the die grinder will be used to remove metal burrs or to cut metal, it must have an RPM rating of over 20,000 and a no-load speed of at least 30,000 depending on the RPM rating.

A die grinder can also utilize additional attachments. The most common attachments are large sanding disks capable of covering more space in a short time. Metric sized couplers can also be handy when using larger or smaller grinding noses.

When running a die grinder, it is important to follow some simple safety rules. Never wear loose jewelry while operating the grinder. Neck chains can easily become caught in the die grinder and cause strangulation. Safety goggles should also be worn at all times.

The operator must keep a strong hold on the die grinder at all times. Similarly, the component being ground should be held in a bench-top vice or clamp. Fingers should be kept out of range of the die grinder. When the die grinder is not in use, it should be unplugged.