What kind of welder do I need?

I'm looking at buying a welder to weld some structural beams into my MK2 to mount a front subframe in the boot. I have however never even tried to weld anything in my life, and consiquently have no idea what I need.

Will I get something up to the job for around 50 (2nd hand obviously)? Seems to be plenty of mig welders on the bay in this price range...

Do I want gas or gasless? What's the difference? I'm not bothered if they're the neatest welds in the world as long as they're strong enough!

Forgive my lack of knowledge, I don't want to hear "you shouldn't be welding something so serious without experience bla bla" there's only one way to learn properly!

 

This is a good website to get some info from.

http://www.mig-welding.co.uk/

Gurds

 

1. You probably want an arc welder for heavy work like that, or a big powerful mig.

2. You're off your rocker, attempting that for a first job.

 

Stay away from arc welders for cars, if you know what you're doing you can just about use them, if you don't you can make a hell of a mess!
Save up some pennies and if funds allow get a second hand professional machine, minimum of 180 amps.
Gasless and hobby machines are usually more trouble than theyre worth. Anything new under 150 is going to be pretty poor.
if you go on the mig welding site, have a word with weldquip as he does semi decent machines at sensible prices.

 

a gas mig...150+ amps

cheap ones will be a pain to use and make you look useless , good ones are eay to get nice results

 

Try to spend some money on a decent MIG welder (150 upwards). Don't bother with the piddly little gas bottles that some machines come with because they run out almost immediately. Go to a welding supplier and get yourself a massive gas bottle, plus a fill of gas, plus a proper regulator. That alone will probably set you back 100+ if you actually buy the bottle, which is what I did. Take care to get a decent quality MIG welder that has a good wire feed. I got a SIP welder from Halfords - one of the smaller machines. The wire feed mechanism on it is utter crap and it's very difficult to weld with (it's a known problem on these SIP machines and I will try to repair it at some point). Also, get yourself a decent electronic welding mask, gloves and protective clothing. Trust me when I say this: trying to weld with crap welding equipment is a bloody nightmare!

This does sound like a totally mad idea for your first major project, but it doesn't mean that you'll never do it. You need to do some welding practice away from the car first obviously. It sounds like most of the stuff you'll be doing will involve welding fairly thick steel which is very forgiving to weld; just practice first so you can weld neatly and achieve the right depth of penetration. For the type of project you have in mind, remember that you'll find MIG welding from underneath the car a total and utter nightmare, so for any work that needs doing underneath I suggest you build a chassis tilter.

I got laughed at when I wanted to do a Syncro conversion as my first major project. So I got stuck in. Never completed it because a genuine 3-door Syncro came up very cheaply and I simply couldn't turn it down. But I built my chassis tilter and I knew I could have definitely finished the project.

 

I bought a Clarke 135, and 150 will just survive on household electrics. Lunched 350 with a mask and regulator, and then went straight round to BOC for a proper argon bottle, rather than the Fisher Price mini bottles they come with from Machine Mart.

Welding does take a bit of time to get used to. I did a course, twice, and just spent loads of time practising, not getting good penetration or making holes. Even now, I will still make holes in metal on the first couple of blasts, because every bit can be different.

 

Maybe, but I was only going to weigh the shell in anyway so I've got nothing to lose

Cheers for the advice, my mate has managed to pick up an arc welder for 50, seems like it might be more up to the job, but if I'm not going to be able to even use it should I just forget that idea and stick with the mig idea?

What's the most powerful mig I'll be able to use without needing three-phase?

 

135 amp officially, but people get away with 150 Amps

I wouldn't mess about with an arc welder on a shell - you'll have a fire.

 

A 150amp, argon, mig welder it is then

 

just a big hole usualy

 

You can go upto 250a on single phase, although they really need a 16a socket or you'll keep melting plugs.
Make sure you have a decent supply whatever you get. Don't go using overlength extension leads, get the car as close to a socket on the ring main as you can

 

got my 150amp mig miles away from the ring and it seems ok, extension lead is pretty big but have melted the plug before. Only doing body repairs atm, but have welded 6mm RSJ's and there fine, well the barn hasnt fallen down yet. Still best to be as close to the ring as possible.

 

All the welding on my mk1 was done with a 300amp pulse mig. Like a car it's good to have some in reserve!

Now you won't be having on of those but practice is the key here. do a search on utube for welding technics, try on the flat first, then when you can do that try down hand etc.

 

make sure its fan cooled too,or it'l keep triping out after continuos use, most modern migs have cooling fans in them , but watch out incase you get some old vintage thing. spend the extra money to on a auto face mask too make life soo much easyier being able to see

 

Neo welds for a living, so you might want to listen to him more than me. An Arc welder should give you better penetration on the thicker metal, but it's a lot harder to get competent with one, and will tend to blow holes in thinner stuff. If the shell's a scrapper, then it's worth a try, but you'll find the rusty bits for sure!

 

x2

saved me a lot of typing.

In the world of welding, 50 doesn't go far, buys you an accessory or 2.

 

As I said I'm looking at buying 2nd hand, I wouldn't expect to get a decent soldering iron for 50 new!

Something like this going to be suitable for me?

 

^^ thats the same as mine and mine is 10years old and has only just starting playing up. Got some very strong welds up to 6mm.

 

Perfect