Review of Millermatic 140 Auto-Set All-in-one wire welding package (sets, repair, electricity)

[reviewer]

We've been looking for a good wire welder for ages. The problem is that these welding tools are expensive, whichever make you buy. While we haven't bought one yet, we've had the good fortune to try this bottom-of-the-range Millermatic on a variety of occasions, and now we're saving hard to get one of our own.
The beauty of this little machine - and it really is small compared to other wire welders, weighing just 60 lb - is that it is requires only single-phase (or 1-phase) electricity (115 V and 20 Amps 60Hz) to operate. Although our house is on three-phases, the workshop only has one-phase. It is incredibly easy and simple to set up and the "Auto-Set" function automatically sets the machine to the correct parameters. As any welder knows, if the parameters are not correctly set, the weld you achieve is likely to have imperfections and even defects. These include cracks, cavities, solid inclusions, lack of fusion and penetration, imperfect shape and pores. Our work had none of these imperfections in spite of our relative inexperience in welding.
There is no guesswork at all with the Auto-Set, you just set the diameter of the wire you are using, together with the thickness of the material you are welding, and off you go. The function accommodates both mild steel and aluminum with the following thicknesses:
o Mild steel that is a fraction of an inch thick (24 gauge or 0.8 mm) to a maximum thickness of 3/16 inches (which is 4.8 mm).
o Aluminum that is between 18 gauge (1.2 mm) and 14 gauge (1.9 mm).
But the machine also has a manual mode that can be used for additional applications.
The Millermatic 140 is intended for light industrial applications including maintenance and repair work, work on cars and trucks, tasks that farm and ranch workers often find they need to tackle, as well as other home-orientated projects for the house and for the garden. In addition to the MIG process, you can also use the machine for flux cored arc welding (FCAW), although we didn't give that a try.
The machine has a rated output of 90A at 18 VDC and its duty cycle is 20%. That means that you can weld for two minutes at a time, and must let the machine cool down in between. A higher duty cycle would be preferable, but for our needs this proved perfect. Other parameters include a welding amperage range of between 30 and 140 Amps, and a wire speed of 15 to 390 IPM.
Another feature that we loved was the Smooth-Smart function which ensures you start the weld without any spatter or popping.
Competitively priced in the middle-range, the Millermatic 140 is supplied with a MIG gun connected to a 10 foot cable. There is also a 10 foot work cable and clamp, and a 6 foot power cord with plug attached. It comes with a Smith Argon and AR/CO? mix regulator/flow gauge and gas hose, two contact tips for .024 inch wire and two more for .030 inch wire and a spool of the thinner wire manufactured by Hobart. The machine also has a factory-installed gas solenoid valve. Its circuitry has been built to ensure that the electrics are "cold" until you pull the trigger of the MIG gun. This of course makes it safer to use and easier to work with.
We also found the set up and operation video very useful, before we used the machine for the first time.