Mig Welding Car Body

[1fifer1]

Hi I want to weld a couple of patches onto my car wheel arch, now disconnect the battery I know but is there any thing else electrical that needs attention?
regards

 

[Craig-SM]

Make sure there is nothing flammable in the surrounding area you’re welding. Something I should have done a better search for.
If you have an air compressor then use an air line to cool the panel whilst welding to prevent distortion and you’ll be doing a series of spot welds to reduce heat build up.

 

[1fifer1]

noted thank you !

 

[the snooper]

noted thank you !

If you want it to last let a piece in, don't weld it over the top, Ive never removed the battery either

 

[1fifer1]

Right not even disconnect the terminals ? I all ways thought it was a must do, thanks any how !

 

[the snooper]

Right not even disconnect the terminals ? I all ways thought it was a must do, thanks any how !

Nope never disconnected anything, unless I was welding a new battery tray in some people remove the connections religiously I never have

 

[1fifer1]

That's good to know feel a lot more confident now thanks

 

[Al Strachan]

You do need to pay a little attention to where your earth goes. if you are welding a wheel arch make sure you earth to the bodywork, not a wheel stud or suspension component. The earth path could potentially be routed via a wheel bearing (bad) or earthing via a tiny sensor cable or small earth strap (very bad).

 

[1fifer1]

so a decent earth strap from the engine to the body should be good enough ?

 

[James1979]

Some cars it's bad to remove the battery. Totally screws with the brain.

I leave it on but always use a surge protector across the terminals

 

[James1979]

so a decent earth strap from the engine to the body should be good enough ?

Just grind up a bit of body to bare metal and earth of that

 

[Mr Roo]

so a decent earth strap from the engine to the body should be good enough ?

i’d probably weld a bolt or a piece of steel onto a non-descript part of the car, relatively close to where you’re welding.

have had earth clamps jump off nearly every existing component when trying to weld cars, so now I just add my own earth point.

 

[1fifer1]

I'm so glad to have started this thread, a wealth of knowledge and experience coming forward, many thanks

 

[Nick DV]

I'm so glad to have started this thread, a wealth of knowledge and experience coming forward, many thanks

That's exactly why this forum is such a good one Lots of helpful and clever people (not me though ) here.

 

[hillman]

When I've struggled to get the earth to clamp on, eg on a sill' I just put an old pair of vice grips on the flange or edge and put the earth clamp on them.
I've got an old pair where the spring has broken just for that purpose.