Milwaukee Tool just announced the next generation of its M12 FUEL 1/4″ Straight Die Grinder, alongside a brand-new M12 FUEL 1/4″ Extended Die Grinder. Both tools ship with a 0.5 HP brushless motor, 4-mode RPM control, and a redesigned grip, and both are sized to replace pneumatic die grinders in metalworking and transportation maintenance work where dragging a hose is the worst part of the job.
What matters for the trade is the spec shift. The original M12 FUEL Straight Die Grinder (2486) ran a 3-mode speed control and topped out well under the 20,000 RPM these new models push. Milwaukee also added a push-button spindle lock for single-wrench accessory changes, a shadowless LED work light, and what the brand calls an improved ergonomic handle. The Extended model (3487-20) gets a 4″ longer shaft specifically for reaching into confined or hard-to-access areas.
Two New Models, One Bare Tool Price Difference
| Spec | 3486-22 (Standard Kit) | 3487-20 (Extended Bare Tool) |
|---|---|---|
| Platform | M12 FUEL | M12 FUEL |
| Motor output | 0.5 HP | 0.5 HP |
| Max RPM | 20,000 | 20,000 |
| RPM control | 4 modes + variable paddle trigger | 4 modes + variable paddle trigger |
| Cutting capacity | 2″ wheel | 2″ wheel |
| Sanding capacity | 3″ disc | 3″ disc |
| Collet | 1/4″ shank | 1/4″ shank |
| Length | 10.8″ | 14.7″ |
| Weight | 1.6 lbs | 1.9 lbs |
| LED work light | Yes (shadowless) | Yes (shadowless) |
| Spindle lock | Push button | Push button |
| Battery platform | M12 (HO XC5.0 + CP2.5 in kit) | M12 (battery sold separately) |
| Price | $379 kit / $199 bare (3486-20) | $249 bare |
How It Stacks Up Against the Cordless Field
Die grinders are a small but stubborn cordless category. Pneumatic still rules in shop environments because the air supply is already there, but on road calls, field welding rigs, and remote fabrication work, dragging 50 feet of 3/8″ hose behind a 1.6-pound tool gets old fast. Milwaukee is making the pneumatic case weaker by closing the power gap: 0.5 HP out of an M12 battery is competitive with the popular pneumatic pencil grinders in the 0.4-0.6 HP range that techs have carried for years.
The closest cordless competitor is the DeWalt DCG426B 20V Max brushless die grinder, which runs 25,000 RPM but on the heavier 20V Max battery platform. The new Milwaukee 3486 is meaningfully lighter (1.6 lbs vs roughly 3 lbs with battery for the DeWalt) and lands in the M12 ecosystem, which most mobile techs already carry a battery for. Makita’s GD001G on 40V XGT is a workhorse in industrial fab shops but is overkill for a mechanic doing brake and exhaust work on a service truck.
What changes the math for buyers is the 4-mode speed control. Pneumatic die grinders run wide-open; the only speed control is trigger modulation. A 4-mode trigger means a tech can lock in 8,000 RPM for stainless scratch removal without feathering the trigger, then jump to 20,000 RPM for porting and chamfer work. That kind of preset speed control has been common on full-size angle grinders for years but is relatively new to the die grinder class.
Who Actually Needs This
The natural fit is transportation maintenance: mobile truck and trailer techs, fleet mechanics, welders, and fab shop hands who need to deburr, port, grind, and finish without dragging an air compressor to the job. The 3487-20 Extended version is built for the opposite problem, getting into exhaust manifold ports, inside frame rails, and other spots where 4″ of extra reach is the difference between pulling a transmission or working around it. For the average homeowner-DIY user, this is overkill. For someone who has been using the older 2486 or running pneumatic, the upgrade is real.
When and Where to Buy
Both the 3486-22 kit and the 3487-20 bare tool are listed on Milwaukee Tool’s product pages now. The 3486-22 kit ships with the bare tool (also sold separately as 3486-20 for $199), an XC5.0 high-output battery, a CP2.5 compact battery, charger, case, and wrench. Home Depot and Acme Tools typically pick up new Milwaukee M12 SKUs within 4-8 weeks of press release. If you are already on the M12 platform, the 3486-20 bare tool is the cheaper way in.
For more on cordless metalworking tools, see our coverage of the Milwaukee M18 FUEL 6″ dual-trigger grinder for heavier stock removal, and our roundup of the best cordless angle grinders for comparison. For the right-angle die grinder format that came before this release, the Milwaukee M12 FUEL 1/4″ right angle die grinder covers the existing M12 die grinder lineup.
Sources: Milwaukee Tool press release, Milwaukee Tool product pages for 3486 and 3487.
