Welding wire ?

I'm a first time welder myself. I was welding trim holes with .030 at first. It was a real tough balance between the two settings on the welder. Once I switched to .023, it was soooo much easier. I say get a fat spool of .025 and weld away. I don't think your welder would be able to weld anything thick enough where you would need .030. Just my opinion.