Rust repairing

[crispy'86]

So i'm going to look at how bad the rust in my notch is and attempt to repir it. My questions are what sheet metal/steel do i need to get my hands on and my welder which is a hobby one , 120amp??? (not too sure there) would it be alright to use that to weld in the new steel? Major areas are in the "A" pillars and inside the boot on my ae85 notchback

[Bling]

What model / minimum amp rating does the welder have? Lower the better, gas will make a nicer job.

[QikStarlie]

a whole sheet of panel steel isnt too badly priced. (cant say i brought any for years tho) if you err on the slightly thick side will make welding it easyer.


if hunting for rust, look under the front guards, mine had rusted quite badly under there.

[CelicaGT8]

120A is more than enough for the usual stuff

[Anth_555]

if you dont want the rust to come back cut it out. dont try to clean it up and put rust kill on that only slows it down

[Stott69]

Sheet = old car door that's in good nic
Welder = TIG, due to its heat range and speed you will get less distortion

[QikStarlie]

lots of quick tacks with mig 5-10mm apart. then go back between. then grind back. is what i'd be doing. also far far nicer to use some new steel.

[crispy'86]

Not sure if my mig is 120 amp, it most likely is lower. I'll definitely be cutting out all the rusty bits and replacing with fresh stuff, now what gas do you guys reccommend? Some say CO2 = alright to use and indoor/outdoor use is alright but get alright weld. Argon= great shielding gas but is not that great when using outdoors and is best under cover and away from wind etc. I'm going to ring couple places to see what's cheaper:: Buying an ownership bottle or renting one

[Adoom]

I rent my Argon bottle off BOC. About $15 a month.
I think if you own your bottle you probably get stung for some kind of safety cert every few years.

I only use old panels for patches if they are a funky shape that would be a bitch to bend up out of a new sheet.
You also have to remove all the paint from old panels before welding....

Is much nicer to weld new steel. I think the generic panel stuff I have used was 0.9mm or something.

[Adoom]

Oh, and make sure you have 0.6mm MIG wire! Welding 0.9mm steel with 0.9mm mig wire is melt-tastic

[Burning Angel]

Some say CO2 = alright to use and indoor/outdoor use is alright but get alright weld. Argon= great shielding gas but is not that great when using outdoors and is best under cover and away from wind etc

The best option is 75% argon 25% CO2, straight Co2 runs hotter than 75/25 and is harder to weld with. straight argon is not used unless your welding aluminium, it gives very little penetration on steel and is probably more expensive.

As to technique, I agree with QikStarlie, tacks spaced out and then filling in the gaps with more tacks, and definitely 0.6mm wire.

Tig will actually warp parts more because compared to mig your going much slower therefore higher heat input.

[LEAKER]

Sheet = old car door that's in good nic
Welder = TIG, due to its heat range and speed you will get less distortion

When welding car panels a Tig creates more heat and more distortion. Using distortion control techniques with a mig and being patient seems to be the answer.

As above Co2 is hotter and probably not ideal but if you do want to go down that route but i use a sodastream bottle. Its about $50 for a soda specific reg from mitre 10 mega and then about $50 for a new bottle which comes filled. THat will do about half an hours straight welding. Then it's $10 or $12 for a refill. Considering the amount of use my mig sees it worked out to be by far the cheapest option for me.
Whatever you do don't go to boc. They're a $&#$% rip off.

[Bling]

Some say CO2 = alright to use and indoor/outdoor use is alright but get alright weld. Argon= great shielding gas but is not that great when using outdoors and is best under cover and away from wind etc.

Don't believe anything those people say. Different gases for different metals / welder types. All gases get blown away in the wind, so what they said is bad 'information'.

CO2 is fine, CO2 argon mix as mentioned above is tidier. I'd lend you my cylinder, but it's near on empty and i'll be using it soon anyway. Renting = best short term, buying better long term IMO. CO2 will be cheaper, my cylinder just happened to come with it, so I use it. Argoshield would probably be better to use, but does cost more.

If you wanted to bring your welder over and have a practise with it on gas, you're welcome to do so. Can fine tune it ready for when you get gas sorted. Offer is there anyway, can give you some hints. Fix some rust on my Corona while you're here

[tsoob]

def mig not tig.

more fill with a mig.

never seen a panel beater use a tig in my whole time in the game.

[crispy'86]

Thanks for the info there guys. It's a pity Toolking isn't round anymore down here. They used to be well priced for co2/argon mix bottle. i tried that and didn't ralise my hose leaked and bloody used it all up through leakage when i wasn't using it.
Might look into suppliers through work for prices on bottles.
Luke- once i get my s%$ sorted i'll come over to yours and work out settings

[Santa'sBoostinSleigh]

MIG and mild steel you want argoshield ideally, about 15L/min according to my professional welder buddy

[Mr Revhead]

And before you start spend an arvo pissing around welding random stuff to random stuff to get the hang of it. Migging is piss easy once you practice a little.

[fangsport]

argon with 0.6 silicone bronze wire. just like using gas but without the heat.
if you have a decent compressor, you could borrow my panel crimper, creates a nice recess for lap joins