OP
Ok. I’ll get that changed out asap. Thanks. Technically he machine says it can do 1/4”. I watched a video on some people actually welding 1/4” and it wasn’t bad. I’ll probably stay away from it though..025? that's good for sheet metal work. you'll burn it up fast runnin welds on thicker material.
.030 will be fine for 16ga up to 7ga. slightly more power to run but less wire fed through the unit.
and .035 for 7ga to 3/8", but 110V kinda keeps you out of this realm. your machine might run the wire but lacks the power to penetrate deep enough to anchor a weld sized for that thick a material.
wire and gas are consumables and you wanna try and keep your cost to operate low.
so gas only needs to be just able to shield the weld, any more is a waste.
with wire, to small a diameter and your gonna burn right through it. if the material can take the heat it takes to use thicker wire, use it.