Miller Maxstar 150 STL TIG Welder Review

For the on-the-go steel welding service, I was looking for a portable, air-cooled, and quite safe TIG welder with good duty cycle of at least 30%. Obviously, my design team would be using it for welding at different sites outside the shop. To be specific, I was in hunt of an efficient welder with sufficient amps for TIG welding steel whose size ranged from 20 to 11 gauge.

After some research and reviews, I found the Maxstar 150 STL welder from Miller to be the most promising one. Till today, I am fully dependent on it for both performance and portability, and it has never let my team down.

What Did I Like In Miller Maxstar 150

Miller Maxstar 150 STL TIG Welder Review

Extremely Versatile in Terms of Performance and Weight

The Miller Maxstar 150 STL unit is versatile from different aspects. First, it works precisely on a variety of materials and switching between DC TIG and Stick via its STL 150 interface. This makes the unit quite flexible for working with small welding projects.

Second, the device is light enough to be carried to different locations due to its shoulder strap and weight of just 13.7lbs. There is no need of cart or trailer at all.

The credit for the lightweight and compact design goes to the embedded inverter technology. For frequent transport, such a technology is essential for eliminating the need for bulky extension cords.

Third, the unit comes with a wide amperage range that is admirable for facilitating more control over a variety of welding tasks. The range allows setting the right amperage on 115 and 23v.

Fourth, this unit runs on either 120 or 220v circuit. The device comes with the brand’s Multi Voltage Plug (MVP) that enables switching between 115 and 230v receptacles by only exchanging out the plug.

This happens without relying on any tools. You only need to select the plug that gets into the receptacle and connect it to the cord.

Adding to the ease of use is the auto-line technology circuitry that associates with the required voltage automatically. This happens without removing the cover.

Stunning Powered Performance

This is possible due to the latest inverter technology. With the help of an inverter-based power source, this Maxstar device ensures an outstanding arc start as well as weld puddle control for both TIG and Stick processes

The Lift-Arc technology allows welding without a higher frequency than normal. The device also comes with a precise amperage control, via a remote control, which allows controlling the welds on thin surfaces.

A special mention goes to the proprietary Adaptive Hot Start invention. This feature aids in preventing electrodes from sticking at the start of the arc. This takes place by immediately enhancing the output amperage at the start of welding process. This also averts an electrode from making an inclusion.

No Gas Valve Required

The unit has a built-in gas solenoid that does not require a gas valve on the torch to make it bulky. This also adds to the lightweight factor and that you can still weld with gas.


There are a few admirable safety features. First, the sow OCV Stick minimizes the voltage to 12 to 16 when the power source is idle. Second, the thermal overload shutoff increases the lifespan and keeps damage away due to overheating. It defends the unit even if the duty cycle is more than normal or when air is blocked.

Third, a fan-on-demand cooling and the wind tunnel technology keeps dirt away and minimizes energy consumption and pollutant intake. Fourth, Line Voltage Compensation (LVC) offers stability in power supply. Lastly, the Power Factor Corrected option prevents breaker tripping.

What I Feel as Limitations

  • Not for aluminum
  • Short TIG torch
  • No foot pedal


The Maxstar 150 STL unit is worth buying for all professionals and welding shop owners who always look for performance in portability.

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Miller Maxstar 150 STL TIG Welder Review
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