problems whilst welding my classic car

[tipi182]

Hi i have bought myself a 1965 105e Anglia in need of restoration, i have bought myself a Cebora 150 turbo mig with a co2/argon mix bottle and using 0.6 wire, i am having problems with blowing holes in the car body whilst trying to weld in new steel.
Iam still learning the art in welding and keep refering to the tutorials on here for help which i find useful, i began by setting the welders voltage to number 1 (goes from 1 to 5) and set the wire speed to 5 (goes from 1 to 10) and practiced on some scrap steel and alterd the wire feed till it sounded right and got some nice welds with good penetration but when i try on the car it just blows holes through the bodywork.
I have cleand the bodywork back to bright steel,,,admitadly the rear of the bodywork has surface rust but i am not sure if this is the problem

cheers
chris

 

[keith19]

Hi Chris, I think you may have diagnosed your own problem.

If the metal is at all rusty behind, and if you have already cut some out, take a piece of it and grind or sand off the back surface to see if it is still covered in rusty pits in the metal. These can easily go more than halfway through the metal, and when you put the mig arc on it the metal just dissolves.

So the metal can look fine on the front, but if it has these rust pits in from behind, you need to cut further back to better metal.

You can try clamping some copper, brass or alloy directly to the back of the weld line, if its accessible, which may help take some of the heat away, and let you continue with the job, but it depends how deep the rust on the back has penetrated.

 

[cortina2003]

dont seam weld,,,spot welds are better for paneling,,work on aternate areas dont allow to much heat to build up,coarse`s distortion!!beware hope it helps

 

[spaffmonkey]

I second the spot welding instead of seem welding.

I spent last week inbetween the rain storms welding my parents

car as it failed the MOT and its so much easyer it did take a while as the size plates i was having to fit but the garage was more than happy and is now after me to be a free lance for them

All the best with your project.

Also when working on there car i welded a short peice of steel to the chassis
to fit the earth clamp to much easyer.

 

[tipi182]

thanks for all your replies, i think like you say about the metal been rusty behind is the most of my problem, it is the front valance which i am trying to repair and even though the front side cleans to a nice bright steel the reverse is quite rusty so it looks like the steel thickness will be reduced somewhat, i like the idea of using copper to reduce heat build up

 

[200T]

To give you an impression how car panels, espacially overlapping ones, rust:

Outside:

Inside:

 

[tipi182]

i see what you mean 200T, so basically like with your images if you tried to weld that panel the metal would "dissolve" like my front valance has been doing, so am i correct in thinking that the metal needs to be rust free on both sides to weld successfully

 

[tombardier]

I think the most important thing is to make sure that the metal is thick enough. you might have it looking shiny on one side, but it could be as thin as aluminium foil, so you will want to be cutting a lot more out than you would think upon cursory inspection, so you get back to some decent solid metal.

 

[Cobbler]

Good liitle car to restore, not many angleboxes left now! I never owned one, driven plenty, some mates had them with wide arches & 1500s in. Went like a rocket. Metal thickness and quality was always a problem, hence the nickname 'Dagenham Dustbin' this may be part of your problems. When well sorted this will be a reliable little car.

Good luck with it

Cobbler

 

[Randall977]

Hi, I'm grappling with a 60's car resto and I'm using a Portamig which will go down to 15A to help counteract the thin metal problem. For almost all of the work I'm using the stitch technique (which you can find a tutorial for on here), it keeps the heat down and looks quite good.

I also have a one sided spot welder (£30 off eBay) which actually works quite well for occassional use on 0.9mm metal and thinner when you get the hang of it.

 

[Chipper]

I have a 180 Cebora and find it fine for bodywork, 0.8mm wire, power on 1, speed down to 3ish sometimes less, I adjust as we go along and find how the metal behaves as it makes a lot of difference with thin stuff. As said, original stuff can be thinned a bit (or a lot...) and manky & rusted.

A heat sink can help sometimes as said, if the original stuff is dubious. Blocks of ally, folded ally sheet, copper etc, anything to do the job.

And patience helps loads too. Pauses, skip about (welds that is, not yrself...), helps with avoiding warping too.

 

[tipi182]

Very interesting all your pointers, as i am newto welding i think i might have had the wire speed set too fast, i have the power on 1 but had the wire speed half way which is 5 , i didnt realise that the wire speed also controls the amps etc,,,,duh lol