E30 Zone

my friend and i are trying to sort(save) a rusty sport, mainly the rear arches need work, bot the seam under the boot seal is pretty corroded(this common?) and a previos owner has crushed a bit of the floor by jacking it up badly, we have an Arc welder we have been learning to weld with and were getting pretty good with it, problem is its easy to blast holes in thin metal 1mm<, how many mm thick are the outer/inner arches? seen some pretty good repairs on here, what are your experiences.. do we need a Mig or can we make do?

id mig it, i managed to blow a few holes in mie with a mig so i think an arc will be even worse, you can get a good enough welder for about 50 notes

been looking at Migs, but havnt seen 1 that cheap, we got the Arc for bargain price of 30 quid. We dont wanna bodge it. are there normally plastic arch liners in the back of an e30? do new outer inners(if that makes sense) get welded all the way round against the wing panels? the outside of the car looks fine so we didnt want to damage paint or distort the metal.

Spot weld or plug weld the 'outer/inners' to the outer panels. Ditch the Arc welder and buy a Mig welder.

The arches are spot welded together around the lip.

That arc welder wasnt cheap at £30 because it is useless for bodywork. Machine mart sell little blue migs for £130 which are perfect for light panel work and exhausts.

Aren't inverter type arc welders meant to be suitable for welding thin gauge steel?

have a look through my restoration thread to see how i fitted my inner rear arches (link in sig below) you will struggle to get them in without at least removing the arch lip so expect to do some painting.good luck

The metal is only 0.8mm thick, there is no way you can put on new outer arches etc with an arc welder.

Look out for a gas mig welder with a lowest setting of 30amps or less (some of the Clarke stuff goes down to 25amps) 0.6mm wire and Argon/CO2 mix gas. The gasless ones will run too hot for thin bodywork.

ok cool, thanx for your input folks, hopefully we can extend this sports life, will create a progress thread and show you how we get on

Definitely get hold of a Mig. Arcs are no good below 1mm and very hard to get right below about 1.6.

My advice would be to try and get hold of a second hand mig. If you are buying on a tight budget a small 'Clarke' or whatever mig will struggle to go low enough to make welding thin sheet easy.

I got a Sureweld Monomig 151 for £50 with half a roll of wire. Good bargains to be had on ebay.

Some of the sealant stuff is fairly flammable so watch out for that. Certainly when welding up the driver's footwell on an E30 the sealant around there would flame up in a very short time.

should get some pics up soon bud let ppl see what your dealing with. id defo go looking for a mig ive seen them go cheap on ebay. where are you located i know of a few going cheap at the moment

your making things difficult/impossible for yourself using an arc on bodywork. buy a mig and spend hours practicing so you are confident you are good enough to not wreck anything, oh and dont skimp on prep. prepearing things properly is the key to good welding i think.
ie making things fit properly before wleding instead of trying to use the weld to fill gaps. and cleaning all metal too a very clean rust/paint free surface or the weld will be full of crap and not very strong.

toby wrote:Some of the sealant stuff is fairly flammable so watch out for that. Certainly when welding up the driver's footwell on an E30 the sealant around there would flame up in a very short time.

Carpet removal is a must

Best way to get rid of sealer is a gas axe/blow torch and wire brush

Oh yeah, don't forget the 6 P's

Proper Preparation Prevents Piss Poor Performance

Have a washing up liquid bottle of water handy, a couple of buckets of water, and a decent sized proper fire extinguisher. Don't weld for more than a few seconds at a time, without checking for fires.
They don't show up too well through a welding helmet.

yeah we have fire extinguisher on hand, and we have been prepping the metal well, for a start its easier to see where you want to weld if its shiney and a good spot lamp on it, believe we wouldnt touch the car until we know what were doing, so now im gonna get a mig and practice till confident. I wanted the Arc welder for making a bike frame and more structural stuff anyhow.

Just found this link...

Thinking of buying a mig welder myself to practice lots with and then work on my car myself so did a search to see what i could find and straight a way came up with this...

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