Ridgid 140 Amp, 120-Volt Electric, Multi-Process Welder

As someone who has spent a fair amount of time in the workshop, I was eager to get my hands on Ridgid's 140 Amp, 120-Volt Electric, Multi-Process Welder, model RMP140. This welder promises versatility and efficiency, and I was keen to see if it could live up to its claims. Here's my detailed take on this tool after putting it through its paces.

Design and Build Quality

The first thing that struck me about the Ridgid RMP140 was its build quality. Right out of the box, it felt robust and well-constructed. The casing is sturdy, and the components seem built to last. Despite its solid build, the welder is surprisingly lightweight, weighing in at just 20.3 lbs. This makes it easy to transport around the workshop or even to job sites without any hassle.

Versatility and Features

One of the standout features of the RMP140 is its multi-process capability. It supports stick, MIG, flux-core, and TIG welding, making it an incredibly versatile tool for various welding tasks. The machine comes with both MIG and stick welding guns, and while the TIG torch is sold separately, the unit includes a gas regulator and hose, which is a nice touch for those looking to expand their welding repertoire.

The welder's inverter technology is another highlight, offering improved efficiency and better control over the welding process. The infinite control for voltage and wire speed allows for fine-tuning, which is crucial for achieving high-quality welds across different materials and thicknesses.

Performance

I started by testing the MIG welding function on 3/16” and 1/4” steel plates using a 0.30 MIG tipped gun and flux-core wire. The results were impressive. The machine provided smooth wire feed and excellent control over the speed and amperage, resulting in clean, strong welds with minimal spatter. The ability to adjust settings infinitely rather than in steps made it easier to dial in the perfect settings for each project.

Next, I moved on to stick welding. The RMP140 handled this with ease, striking and maintaining a stable arc even with my somewhat shaky beginner's hand. The welder supports rods between 1/16” and 1/8” thickness, and I found it capable of welding mild steel up to 1/4” thick without any issues.

For TIG welding, I had to purchase the torch separately, but once set up, the machine performed admirably. The TIG feature is capable of welding up to 3/16” thickness, and while my initial attempts were less than perfect, the welder's consistent performance allowed me to improve with practice.

Ease of Use

Setting up the RMP140 was straightforward, thanks to the clear and comprehensive 27-page manual. The single connector for the MIG gun simplifies setup compared to other welders that require multiple connections. The side panel opens easily to a vertical position, making it convenient to swap spools of welding wire.

One small gripe is the lack of storage for the spool holder when using smaller spools, but this is a minor inconvenience in an otherwise well-thought-out design. The machine also includes a polarity adapter for MIG welding and a switch for selecting between MIG, TIG, or stick welding, all easily accessible on the front panel.

Power Requirements and Duty Cycle

The RMP140 runs on a 120-volt input, making it suitable for most standard outlets. For thicker materials requiring higher amperage, Ridgid recommends using a 30-amp outlet, although it can run on a 20-amp outlet for lighter tasks. The welder includes an adapter for switching between 20-amp and 15-amp circuits, adding to its versatility.

The duty cycle is 30% at 90 amps for MIG welding, which is typical for welders in this class. This means you can weld for three minutes out of every ten without overheating the machine. During my testing, the welder stayed cool and didn't trip the breaker, even during extended use on a 20-amp outlet.

Maintenance and Warranty

Maintenance is straightforward. The welder uses standard TWECO tips, readily available at most welding supply stores. Ridgid recommends removing the side panels every six months to blow out any accumulated dust with compressed air, ensuring the machine stays in good working condition.

The RMP140 is covered by Ridgid's 3-year limited lifetime non-transferable warranty, which covers wear and tear or failure under normal usage and proper maintenance. To qualify for the warranty, you need to bring the welder to an authorized Ridgid service center.

Final Thoughts

Overall, the Ridgid RMP140 is an excellent multi-process welder that combines versatility, ease of use, and robust performance in a lightweight package. It’s perfect for hobbyists, DIY enthusiasts, and those needing a reliable welder for light to medium-duty tasks around the home, farm, or workshop.

Would I recommend the Ridgid RMP140? Absolutely. Its ability to handle multiple welding processes, combined with its user-friendly design and solid build quality, makes it a valuable addition to any workshop. Whether you're a beginner looking to learn the ropes or an experienced welder needing a versatile tool, the RMP140 is well worth considering.