Earthing tricks

[inchpincher]

Sometimes I find this a real headscratcher if I'm trying to tig small ali parts because my earth clamp is a bit industrial. I find the hf struggles if I just clamp to the bench or the part sometimes fuses to the surface where it's made a circuit... Any tips from the old hands?

Eg how would you get an earth on a curved ali fuel tank?

 

[brightspark]

Sometimes I find this a real headscratcher if I'm trying to tig small ali parts because my earth clamp is a bit industrial. I find the hf struggles if I just clamp to the bench or the part sometimes fuses to the surface where it's made a circuit... Any tips from the old hands?

Eg how would you get an earth on a curved ali fuel tank?

strap a braided battery earth lead round it and a good laggy band to hold in position

 

[gordon stephenson]

I have a piece of heavy welding cable about 3 feet long with the rubber insulation stripped off and just the ends soldered to stop them unravelling . Just wrap it around the item and clamp earth onto it,Don't have any problems with arc-strike with thousands of tiny copper contact points,

 

[Shox Dr]

Using the bench or forgetting you have clamped to the bench can be a real problem if you are welding Brushed or polished Stainless or alloy for that matter, It can mark the piece up real bad.

I have no fix all suggestion, other than making sure the return lead has a good contact with whatever you are welding

 

[pedrobedro]

Piece of wire in your earth clamp leading to whatever you are welding then clip it on with a small crocodile clip.

 

[hotrodder]

I often use a small (toolmakers/welders/vicegrip) clamp and clip the welders return lead to that. In the case of the fuel tank example sender holes/inlets/outlets are likely suspects if you don't want risk scratching it somewhere visible.

Small/fiddly things i tend to hold still with something often known as a 'welders finger'... http://www.flickr.com/photos/12493141@N07/3341446758/, basically anything which has enough mass to hold it still (without getting in the way) and improve contact. A more direct version here...

 

[inchpincher]

All good advice, thanks, I'll make a couple of those welding fingers tomorrow and butcher the old earth cable from my mig.