You can weld in your garage with the doors opened and it raining. The only problem with moisture is it can cause rust on freshly grinded & clean metal. But you'd have to let it sit for a bit before that would become an issue (flash rust). If it happens, just grind the metal again enough to get the rust off. Like anything else, preparation is key to a final product. You want your metal as clean as you can get it (the portion that is being welded that is). If you don't have a grinder, that is an absolute must for welding. Unless you would enjoy using a file...you could also use a belt sander, etc. But a grinder is basically a component part (and a sturdy wire brush). If you don't have one and you don't see yourself tackling big projects, a 4 inch grinder is fine. If you you have a metal band saw or something like that, weld two pieces of 1/4" or 3/8" steel together and then cut right down the middle of the weld. You should not see in the cut little holes or slag that got caught in the weld or anything. As you weld with your MIG there will be little bits of slag that is thrown around and will adhere itself on the metal. You'll see. You will also see the black soot and beige remnants of the flux. Every time you stop, you need to clean that away from where you will be continuing the weld. If you don't that stuff will end up in your weld and will weaken it (that's why the cut test). Break out the wire brush and get that next area thoroughly cleaned of that junk. A wire brush on your grinder or similar device (air tool) can make things quicker and easier.

As far as temperature, the hotter the metal is, the quicker the puddle will develop. But you can weld in freezing temps no prob...as long you get the metal flowing properly. You will also notice that as you weld that metal will of course get hotter and hotter. You don't want to weld to the point of it deforming, so know when to stop and let it cool down a bit (that's where the wire brush) comes in to play.

that welder probably cant do over 1/4 inch steal. it should say in the directions. i have a fluxcore century welder and it CAN do 1/4 inch steal if the steal is good and hot and you crank the heat and go a little slower on the speed.

also make sure you wear that mask, its not just there to protect your eyes. one of the first things i welded was shock tabs on a axle and just used the lens cause i was in a tight spot. ended up having a nice sun burn the next few days

expect it to take a while. id say i went through about 4-6 lbs of wire before i got good

Yeah it says it can do 1/4" I'm pretty sure, but I'm not expecting much out of it. Since I've never welded, I don't have huge expectations for it. Actually it says it can do 1/4" with multiple passes. But going by that logic, couldn't you technically weld any thickness?

No, not any thickness. You won't get enough penetration if you don't have enough amperage. When your welding 1/4", you want to grind the edges to a 45-60 degree angle, creating a 'v' between the two pieces. That's how your doing the multiple passes.

ive tried to weld 5/8th plate to 5/8ths plate before, i couldnt get penetration for anything. basically i was working on this giant push bumper thing and was just trying to tack the brackets on where i needed them to be so i could weld it at work and yeah it didnt like it at all.

Here are a few welds I did the other day, on a trailer I've been working on. What do I need to do better?
https://blazerforum.com/forum/attach...ine=1401758255

https://blazerforum.com/forum/attach...ine=1401758255

https://blazerforum.com/forum/attach...ine=1401758255

I'm thinking the wire speed was too high?

i've seen and done worse - first pic you just wasn't steady and consistant enough - other two don't look bad for a flux weld

I'm also not as concerned about the welds looking nice as I am about them being strong obviously

A Quote from my FFA instructor too many years ago - [hel- it's a good looking weld as long as it dosen't look like a chicken squated on the metal] - looks like you have good penetration from what i can tell in the pics {blueing of the metal around the beads} as stated above first one just not as consitant enough with bead - the only other thing is you didn't quite start at the edge and stoped before the edge - IMO from what i can see your doing fine

Haha that's what I look for.. does it look like bird crap? No? then its fine