Milwaukee 4-1/2" / 5" Grinder

Milwaukee's 4-1/2" / 5" Grinder, model 2781-20, has quickly become an essential addition to my tool collection. As someone who frequently engages in grinding, cutting, and surface preparation tasks, I've found this cordless grinder to be a game-changer in terms of convenience and performance.

Performance and Power

The first thing that struck me about this grinder is its power. Despite being cordless, it delivers performance comparable to many corded models I've used over the years. The brushless motor is a standout feature, providing enhanced durability and efficiency. I’ve used it on various materials, from metal to concrete, and it has consistently performed without a hitch. The grinder operates at 8,500 RPM, which is sufficient for most tasks I encounter.

Battery Life and Convenience

One of the primary concerns with cordless tools is battery life. While the Milwaukee 2781-20 does consume a fair amount of battery, especially under heavy use, it’s a trade-off I’m willing to accept for the convenience of being cord-free. I recommend using a 5.0 Ah battery or larger to get the most out of this tool. The 5.0 Ah battery strikes a good balance between weight and runtime, but for extended projects, you might want to consider the 9.0 Ah or even the 12.0 Ah battery.

Ergonomics and Design

At 5.8 pounds, the grinder is lightweight and well-balanced, making it comfortable to use for extended periods. The slim design and narrow head allow me to get into tight spots, which is particularly useful when working on detailed projects or in confined spaces. The paddle switch is easy to engage and provides a good level of control, although it does take some getting used to if you're accustomed to a slide switch.

Safety Features

Safety is always a priority, and Milwaukee has incorporated several features to ensure user protection. The tool-free guard adjustments and accessory changes are incredibly convenient and minimize downtime. The grinder also includes advanced electronics for overload protection, which adds an extra layer of security when pushing the tool to its limits. However, the safety lock-out for the paddle switch can be a bit cumbersome, especially when wearing gloves.

Durability

Having used this grinder in various environments, from home workshops to construction sites, I can attest to its durability. The brushless motor not only extends the tool's life but also reduces maintenance needs. The build quality is robust, and the tool has withstood being tossed into tool bags and subjected to job site debris without any issues. The five-year limited warranty is a testament to Milwaukee's confidence in their product, though I haven’t had to use it yet.

Versatility

The Milwaukee 2781-20 is incredibly versatile. It accepts a range of grinding and cutting discs, from 4.5 to 5 inches, and the 5/8"-11 arbor size is compatible with most accessories. I’ve used it for everything from cutting rebar and grinding welds to removing rust and paint. The tool-free accessory changes make swapping out discs quick and easy, which is a significant time-saver.

Noise and Vibration

One of the pleasant surprises was the relatively low noise level and reduced vibration. While no grinder is whisper-quiet, this model is less jarring than many corded versions I've used. The anti-vibration handle is a nice touch, making it more comfortable to use over long periods and reducing fatigue.

Areas for Improvement

While I’m generally thrilled with the grinder, there are a few areas where it could be improved. The paddle switch, while functional, could benefit from a more intuitive safety mechanism. Additionally, the FIXTEC nut, designed for tool-free accessory changes, can sometimes seize up, requiring a wrench to loosen. This isn’t a deal-breaker but can be annoying when you're in the middle of a project.

Final Thoughts

In conclusion, the Milwaukee 4-1/2" / 5" Grinder, model 2781-20, is a powerful, versatile, and durable tool that excels in both performance and convenience. It’s well-suited for professionals who need a reliable grinder that can handle a variety of tasks without the hassle of cords. The robust build quality and thoughtful design features make it a worthwhile investment.

I highly recommend this grinder to anyone in need of a high-performance, cordless option. Whether you're a professional welder, a construction worker, or a DIY enthusiast, this tool will not disappoint. The convenience of cordless operation, combined with the power and durability Milwaukee is known for, makes it an excellent addition to any tool arsenal.