Angle grinders are too large for precision work in tight spaces. A die grinder is an inline tool that spins attachments at up to 25,000 RPM. Mechanics use them to clean engine block gasket surfaces, deburr cut tubing, or port cylinder head intake runners. They run on compressed air or batteries. Swapping a carbide burr for a wire wheel or a surface conditioning disc allows you to clean up parts quickly. Wear ear protection, as pneumatic models are loud.
Mechanic Glossary
Die Grinder
A high-speed, compact rotary tool used with carbide burrs, mounted stones, or sanding drums for precision metal grinding and porting.
Frequently Asked Questions
Straight die grinders are inline like a pencil, making them good for reaching deep holes. Right-angle models have a 90-degree head, which is easier to control on flat surfaces.
No. Automotive die grinders spin too fast and will burn wood bits. Use hardened carbide burrs designed for steel and aluminum.
These are round, abrasive pads (often called Scotch-Brite discs) used to clean old gasket material from aluminum parts without removing metal.
Put 2 to 3 drops of air tool oil into the air inlet before each use to lubricate the internal rotor blades.