[bsccp]

OK here's my .02. Strictly an amature DIY, but here's what I've learned over the years.
I bought a Hobart 125 Handler at HF and then added the gas kit, about $100 plus bottle purchase or lease. Personally I started using a gas mix of 90% argon and 10% CO2. OK, I know most people will say why don't you use 75/25? Far easier to find. I did a '65 Mustang fb, both floor pans and trunk and very rusty. Pros will say that the 90/10 runs hotter but with the limited power settings of the Hobart I found good penetration on 18 ga without too much heat.
I've used flux core for exterior work and it works very well. I use wire from a welding store, E-7, just for reproduceable results. Flux core comes in .030 while gas wire will come in .023 or .024. FYI check your tips on to make sure they are correct size!
Two items I think help when using MIG. MIG pliers ($8 HF) to clean and replace tips, cut wire etc.. Welding jelly (antisplatter). Don't know exactly what it is but if you lubricate the tip (no jokes please) and shield I get cleaner welds with less splatter. Also, there is a spray antisplatter that helps but surface prep is essential.
Used old school helment with flip down for years and had to add filters because I got a terrific headache with the OEM filter. My welding buddy let me use his $300 auto darkening helment and it is wonderful and makes welding much faster and no headaches!
I'm currently doing a S10/'51 GMC project and have found that the weld penetration on the frame and motor mounts are pretty solid. I used 3/8" plate for the motor mounts and it looks and feels solid. The frame mounts are all 1/8" and I get great welds. 120v Hobart. My welding buddy has a 220v Hobart and will finish off the structural welds just because his welds are much nicer! Less grinding. I know that 16-18 ga will be no problem with the same rig.
Just like painting, preparation is key. Vertical welds take patience and a fraction of a second between puddles helped me to avoid runs.
Just my opinion but it is satisfying.
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