Thread: MIG welder - should I HIRE one?

The common misconception with MIG is that it's just 'pull the trigger and go'. You end up with a nice shiny weld, yet it's crap and hasn't penetrated. If you own a stick welder or could borrow one from a friend for free, then buy some 25x3mm flatbar, cut it up and practise but-welding it together.
If you don't, just hire a mig and do the same thing. Hold it perpendicular (straight up) from the workpiece, then tilt it 20° to the right (so it's 70° from the workpiece). With stick you would pull or drag it along, with mig it's a pushing operation, holding the torch about 5mm above the work.

The other thing is, how long do you plan on hiring for? The amount of welding you get done in a weekend is often less than you'd think. Organise some flatbar as I said, in about 100mm lengths, but weld them with a 1mm gap and check underneath, it should've penetrated through a bit. Spend say... A couple of hours on a friday afternoon for that. Then say, 30 mins the next morning practising on off-cuts of what you plan to weld, so you can get the settings right. The rest of the weekend could be for the project.

Hi

Edd is right about the mig looking good but maybe not penetrating.

If it is for racking and not structural (house or whatever) then I would suggest hire the mig, use gasless wire, crank up the amps and practice on the bottom sides so no one can see if you blast through. Then turn it back a bit. Dont forget to adjust the feed rate as you adjust the amps.

When I was a mechanic my old man had this habit of trying to stick weld at 8am on a sat after I had been out the night before;

Bsssssssssssst "jkldasjfadjl" bsssssssssssssssssssssssssssssssst "dkfjkdjdjaijfsj bsssssssssssssssssssst "asdfjhfaddsahfdshfjadshjdhj".

Go for it!

cheers

dazzler

One other thing, if you want to hire it with gas, go for Linde cylinders. My father and I went up to the goldcoast and did some mig welding for a friend and we needed to hire gas there for about 3 days. BOC said they will have to charge us for 6 months rental and probably the whole cylinder of gas. Linde didn't charge rental and charged for the gas we used. It cost about $12
If you want to use flux-cored wire you could do that too, but it might not end up being too much cheaper if you're only hiring for a short time. Despite the fact I'm not to fond on gas-less wire, the speed advantage of mig will hold true with that, so it's still pretty good for most things.