..or weld a larger surface area if possible. It *can* do it if you really need it to, but to handle the bare minimum means running the machine at its maximum capacity so you're only going to be able to weld at about a 10% duty cycle, so even if it is handling it your machine is going to run warm and it might take a while. Being that its a 120v unit also brings challenges of its own as a standard outlet isn't designed to handle the power. I don't know if you've run into issues yet, but it may not be a bad idea to upgrade an outlet in your shop to 12 ga wire and throw a 20 amp plug/breaker on the setup to handle the welder better.
125 amps is pretty small, but I did build my first utility trailer 15 years ago with a ~130 amp flux core 120v Lincoln and its still holding out fine (all 1/4" construction and it regularly sees heavy gravel/dirt loads). Its not the most ideal setup, but if you prep everything well and have a little bit of patience then you should be ok. Do some test welds on similar material and post up some pics so we can see how they're looking. LR
'09 Ford Ranger FX4 that gets abused a lot... but doesn't like to swim though.