A different question for welders....

[txfireguy2003]

Okay fellas, I recently came into possession of a Millermatic 180 mig welder. I've mig welded before with someone else's machine, but I've never owned one. My other machine is an engine drive stick welder, and my bother's machine is a small flux core only machine. My new mig didn't come with a gas bottle, but I know I want one, but them bottles are EXPENSIVE! How big of a bottle do I really need? I know that question is hard to answer without knowing how much welding I will be doing, so I'll answer that by saying that it really depends! I may go months without ever striking an arc, but then I might weld every evening and all weekend for a month or two building a large project like a trailer mounted smoker or something. I like to run the 10lb spools when using the flux core machine so I'm not swapping out the spools as often, and I'm sure I'll be doing the same with the new mig. How much gas would it normally take to run a full 10lb spool? I figure the 20cf bottle is too small, as I know with my oxy/ace torch, I'm having to get those little bottles refilled all the dang time, seems like every time I go to use it, I have to run to the welding shop, it really gets old, especially since 99% of the time, I'm welding (and running out of gas) when the welding supply house is closed. What about a 40cf? The 80cf runs about $300 from what I've seen, which is doable, but really more than I wanted to spend right now, but if that's what I really need, that's what it'll have to be. Can I run through a full 10lb spool of wire without refilling an 80cf bottle?

Also, I know it depends on the type of metal and wire used, but what is the best gas to use? I'm mostly welding mild steel, but will occasionally weld stainless, is there a gas that works for both of those? I know aluminum requires straight argon, but that's a ways out, I'd need a spool gun first anyway.

Thanks for all your help in advance guys.

[Dale Moser]

You want a big one.

[Dale Moser]

A different question for welders....

I think they are 34 cf or so, some Home Depots have an exchange. They call it Stargold mix.

Also make sure the polarity is right. If they weren't using gas then you will need to switch it.

Congrats, that's the mig machine I have and it's a stud for a small box. Burn .035, don't mess with .030 unless you are doing body work.

I didn't read the whole thing, as I'm on my phone.

[Dale Moser]

If you want to do aluminum you will need pure argon.

[Hoggslayer]

I think it just to big of a hassle and you should let me take it off your hands.

Get the big bottle.

[Dale Moser]

Seriously, if you're prone to locking yourself in the shop for a long weekend burning on a smoker...you want the big bottle. You can have an extra roll of wire, gas will shut you down when it runs out.

[txfireguy2003]

Yeah, that's kinda what I figured DMo, I'm just not sure what is defined as "big". The welder I used when I worked for a welding shop in high school was a bigger Lincoln and the old man had a bottle that stood about 5 feet tall and weighed a metric ton. Loading it in his truck for him to go refill was a chore, but I can only remember doing that one time and we welded pretty much non-stop from the time school let out until dark every night, and all day on Saturday and all afternoon on Sunday after church. It was almost constant arc time too, because there were two of us that worked for him. One would sit at the horizontal band saw cutting tubing to length while the other would slap pieces in a jig and weld them up. He had a big saw too, so it was easy to stack 12-16 sticks of tubing, clamp them all down and cut multiple copies of the same part all in one pass. We worked for him for pretty much our whole senior year of high school and I can only remember loading that bottle up to refill once. I'm sure it was filled other times that I wasn't aware of, but maybe not, the shop wasn't running during school hours because it was his side business as he was a band director at the high school. I guess what I'm looking for is a rough estimate of trigger time per cubic foot of gas.