The 10 Best Die Grinders

With a decent compressor, the Ingersoll Rand 3107G is the straight die grinder to start with. It spins at up to 27,000 rpm, and its rear exhaust blows air back past your hand, away from the work. A composite sleeve keeps the grip from turning icy, and a safety lever must be flipped before the throttle moves. The catch is air: under load it wants about 18 cubic feet a minute, more than a small compressor can supply.

The Chicago Pneumatic CP860 is built for body shops and fabricators who grind all day. Its motor is rated at just over half a horsepower, so it slows down less when a carbide burr bites into steel. The barrel is bare aluminum, the lever locks off against bumps, and the maker backs it for two years. It drinks more air than most home compressors supply, and one retailer lists it as discontinued.

Edges, the insides of pipes and the backs of brackets are where the Ingersoll Rand 3101G earns its keep. Its head turns the bit at a right angle, reaching spots a straight grinder can't get square to. A motor rated at a third of a horsepower drives it, and the throttle locks itself when you let go. Its top speed of 20,000 rpm trails straight models, so polishing takes a little longer.

Starting out cheaply? The WORKPRO W182004A arrives with both common collet sizes, two wrenches, an air plug and a bottle of oil. Its small aluminum body wears a red rubber sleeve and runs at up to 25,000 rpm. WORKPRO publishes no horsepower rating or warranty terms, so you're betting on a brand with a short record in air tools. A few drops of that oil in the inlet before each session keep it turning freely.

No compressor? The DeWalt DWE4887 plugs into the wall, and because it runs on AC or DC power it also works off many welding generators. It spins to 25,000 rpm, and the paddle switch under the barrel shuts it off as soon as you let go, with a button to lock it on for long passes. DeWalt backs it for three years. It's heavier and longer than an air grinder, so it tires the wrist sooner overhead.

Out on a site with no air line or outlet, the Milwaukee M18 FUEL 2984-20 runs on Milwaukee's larger cordless batteries. It offers five speed settings, a light near the nose and a brake that stops the bit about two seconds after you release the paddle. A phone app can set speeds and keep track of it. It's sold bare, so a battery and charger cost extra, and its weight makes delicate work tiring.

Under dashboards and inside frames, the Milwaukee M12 FUEL 3485-20 fits where bigger grinders can't, with a right-angle head on a grip small enough for one hand. Pro Tool Reviews notes four speed modes topping out at 20,000 rpm and a spindle lock that makes bit changes quick. It runs on Milwaukee's compact M12 packs, which aren't included. This one comes from an outside seller rather than Milwaukee's usual dealers, so check what's in the box.

Quieter shop time is what AIRCAT aimed for with the AIRCAT 6255. A tuned exhaust holds it to about 82 decibels by the maker's figure, and a light feather trigger lets you ease the speed up for delicate passes. The angled head and the red composite grip with rubber inserts suit deburring in tight corners. Its top speed of 18,000 rpm is modest, so heavy stock removal goes slower. AIRCAT covers it for two years.

Think of the Astro Pneumatic 218 as an air-powered pen for engraving, porting small passages, cleaning molds and touching up welds in tight seams. It spins small-shank bits at up to 56,000 rpm, and a twist collar on the body sets the speed. A flexible hose keeps the weight of the air line off your fingers. Full-size bits won't fit, and with so little torque it stalls if you push hard into steel.

For indoor shops where noise carries, the Makita GD0601 is a corded grinder rated at 73 decibels, low for a power tool. Its slim barrel is easy to wrap a hand around, it runs on AC or DC power, and it reaches 25,000 rpm. A slide switch on top turns it on and can lock it running. There's no lock-off to keep it from being bumped on, and it's heavy enough to tire a wrist in long sessions.