Makita 4-1/2" Angle Grinder

As a long-time user of various power tools, I recently had the opportunity to work with Makita's 4-1/2" Angle Grinder, model 9557NB. This compact yet powerful grinder has been a staple in many professional and DIY toolkits, and after putting it through its paces, I can confidently say it lives up to much of its reputation, albeit with a few caveats.

Design and Build Quality

The first thing that struck me about the Makita 9557NB is its robust construction. It features a labyrinth design that effectively seals the motor and bearings from dust and debris, a crucial feature that extends the lifespan of the tool. It’s clear that Makita has put significant thought into durability, with all-ball bearing design and metal gear housing that feel solid and dependable.

The grinder’s compact design is another notable aspect. At 10-5/8" in overall length and weighing just 4.5 pounds, it’s easy to handle even during extended use. The small circumference barrel grip (2-1/2" diameter) significantly enhances comfort, making it less taxing on the hands and wrists. However, for those with larger hands, the grip might feel a bit too slim.

Performance

Under the hood, the Makita 9557NB is powered by a 7.5 AMP motor capable of delivering 11,000 RPM. This high output power makes it highly efficient for a range of grinding and cutting tasks. I found it particularly effective for metalwork, where the constant speed helped in achieving a smooth, even grind.

The motor's performance remained consistent throughout my testing period, with no noticeable drop in speed or power, even under a load. The thicker coil wires in the motor reduce heat and energy loss, contributing to its robust performance. It feels like a workhorse that can handle demanding tasks without faltering.

Ease of Use

One of the most user-friendly features of the Makita 9557NB is the AC/DC switch, which allows for use with alternate power sources. This flexibility can be a lifesaver on job sites where power outlets are scarce or at a premium. The slide switch with lock-on function is designed for continuous use, which is great for longer tasks. However, this switch has also been a point of contention.

The On/Off Switch Issue

The slide switch, while convenient for continuous operation, has a few drawbacks. Engaging the switch can be awkward and requires a bit of force, which might be inconvenient for some users. More concerning is that the switch can jam, especially when used in dusty environments, making it difficult to turn off or on. This issue is something Makita should address in future iterations, as it can hamper the overall user experience and poses a potential safety risk.

Safety Features

The grinder includes a protective zig-zag varnish that seals the armature from dust and debris, adding an extra layer of protection. The side handle can be positioned on either side of the tool, providing flexibility and better control. While these features are excellent for safety and durability, the on/off switch design detracts from the overall safety profile of the tool.

Durability

Durability is where the Makita 9557NB truly shines. Many users, myself included, have found that this grinder can withstand years of hard use. The all-metal gear housing and bearings contribute to its longevity. It's not uncommon to hear of these grinders lasting over a decade with regular use, which speaks volumes about their build quality.

Versatility

The grinder's 4-1/2" wheel diameter is versatile enough for a variety of tasks, from cutting metal and stone to grinding down surfaces. Changing the grinding discs is straightforward, although I would have appreciated a tool-free guard adjustment. The current design requires a screwdriver, which can be a bit of a hassle if multiple adjustments are needed during a project.

Noise and Vibration

In terms of noise and vibration, the Makita 9557NB performs well compared to other grinders in its class. It runs smoothly and with minimal vibration, which reduces user fatigue. The noise level is also relatively low, making it more comfortable to use for extended periods.

Final Thoughts

The Makita 4-1/2” Angle Grinder (9557NB) is a reliable, durable, and powerful tool that offers excellent performance for a variety of grinding and cutting tasks. Its compact design and robust construction make it a valuable addition to any toolkit. However, the on/off switch design is a notable drawback that Makita should consider refining.

Would I recommend this tool? Yes, but with reservations. If you're in the market for a sturdy, high-performance angle grinder that can handle heavy-duty tasks with ease, the Makita 9557NB is a solid choice. Just be prepared to manage the quirks of the on/off switch, especially if you’ll be working in dusty environments. Overall, its durability, power, and ease of use make it a worthwhile investment for both professional and DIY users.