Chassis welding

Last weekend I found some holes in the front dumb irons. I need to plate these which isn’t a problem, as the MOT isn’t for another 4 weeks.

The problem is what to weld with, MIG, TIG, MMA? At work we have a 3 phase MIG, that I’m very handy with. Been welding with it for the last 4 years, can run 2 1.2mm sheets together, or large 1”thick bearing shells. I won’t be stripping the car at work. At home I have a 180A AC/DC TIG, a 170A Stick, and a hobby (Clarke) MIG. The mig is currently on gas, but isn’t that great.

What would you use to repair the dumb irons? Would you use the MIG at work and trailer the Defender up and back? I don’t own a trailer or a vehicle capable of towing the defender on a trailer. Or would you use MIG/TIG at home? I know I can make the MIG welds strong enough, not sure about the TIG though, as I’m not great with TIG. I will be using 2-2.5mm sheet mild steel for the repair.

I would do with MIG and Argomix and 3mm steel.

Mig imo

tottot said:

I would do with MIG and Argomix and 3mm steel.

Click to expand...

I don’t have any 3mm plate, just 2 and 2.5mm.

I want to do it all with MIG, but it’s the hassle of transporting it to and from work.

Mig and Argo-mix would be easiest. Mig is a bit more "dirt-tolerant".
You can get 3mm mild steel sheet off-cuts delivered to your door via e-bay. Not the cheapest way but dead easy.

mick 1986 said:

I don’t have any 3mm plate, just 2 and 2.5mm.

I want to do it all with MIG, but it’s the hassle of transporting it to and from work.

Click to expand...

Chassis was only made in 2mm thick steel, absolutely no advantage to going thicker.

2mm plate would go easy enough with a stick welder using 2mm or 2.5mm rods and a stitch at a time.

MIG would blast it in there good and fast, depends on what type of repair you're planning on though, over plating, cutting it out and welding in a whole new section?

dieseldog69 said:

Chassis was only made in 2mm thick steel, absolutely no advantage to going thicker.

2mm plate would go easy enough with a stick welder using 2mm or 2.5mm rods and a stitch at a time.

MIG would blast it in there good and fast, depends on what type of repair you're planning on though, over plating, cutting it out and welding in a whole new section?

Click to expand...

I’m thinking of cutting it out, then putting in the plate and welding the seam. I really would rather MIG, but it’s an arse about getting it to work and back.

Any of them will do the job. If you feel most comfortable with Tig, and can put in the time to clean it all up before hand, you could just as well use that.

99.999% of the time that kind of job will be done with a mig, but there's no reason (other than cleaning) that you couldn't do it with a Tig. I doubt you'll ever get it clean enough to stop contaminants comming up to the surface, but if you can suffer that, it will do the job just as well.

julianf said:

Any of them will do the job. If you feel most comfortable with Tig, and can put in the time to clean it all up before hand, you could just as well use that.

99.999% of the time that kind of job will be done with a mig, but there's no reason (other than cleaning) that you couldn't do it with a Tig. I doubt you'll ever get it clean enough to stop contaminants comming up to the surface, but if you can suffer that, it will do the job just as well.

Click to expand...

Thanks for the reply. I can put the hours in at home, so should be able to get the repair panel and the chassis sections clean enough. I have a few different flap discs and wire wheels for the grinders and drills.

I’m happiest with MIG, then stick, then TIG, but my most able machine (at home) is the TIG. I think that settles it. I will have a go with the TIG, but don’t laugh too much at my welding. It’s not the prettiest with the TIG, but it sticks!

Use the stick then, I'd probably find it easier with a stick and I find it just as easy as MIG on plate 2mm and above.

Don’t forget a grinder and a slap of paint can hide a multitude of sins