Earthing.

[Cracker]

Hi everyone. I have a workbench made out of a steel frame connected to the concrete garage floor and walls with an aluminum sheet as a protector for the wooden top.
Could I use that as an earth for my mig welder.

 

[Mark 2]

The return (earth) needs to connect to the alu sheet - if that's what you are asking.
Welcome to the forum.

 

[brightspark]

whats the point .the return earth clamp needs connecting to the work piece not the table to get a solid connection

 

[nickk]

Good principle,clamp your earth as close as possible to the area your laying the weld bead.

 

[BrokenBiker]

yes you can (to the ali), just be weary of parts that dont sit perfectly flat or are only touching the ali with a small contact area as this can cause arcing...

i generally earth to the table, lets me move the part around freely but if im having issues i will earth to the part

 

[Maxakarudy]

What about an earth rod?

 

[mr haynes]

I misread, thought there was an "L" in the title and in a first contact situation.....

 

[zzr1200]

I maybe wrong, but:-

I think the OP is asking if he can use the aluminum sheet covering the wooden surface on his bench as an earth conductor for the welder.....

Personally I'd want a steel surface plate with a minimum 6mm thick on a small welding bench.

 

[MikeBs]

I use a similar setup to the OP’s suggestion but with a 2mm sheet of stainless as protection for the table. Not ideal but it’s all I have.
It works, but pieces often stick to the stainless and need to be levered off with a screwdriver. It’s not a problem if I’m working with items robust enough to be levered off. When I’m making something more fragile then getting the earth point closer to the weld is needed.

 

[Mark 2]

Perhaps he's been frightened off now he's gone through the initial 'welcome, question answered' phase.
It's a shame really, as the second phase of 'use the search and punishing sarcasm' does tend to be the backbone of this forum.

 

[Cracker]

Thanks for the replies. I couldn't get back last night as I had to shoot off out. However I think I've sorted it out, I've put a substantial bolt through the work bench and I'm getting continuity using a multimeter. What I want to do is place two pieces of metal flat on the bench to practice butt welding rather than having to clamp the earth cable to one of the pieces. I've tried to send a photo, but I can't do it.

 

[BrokenBiker]

Thanks for the replies. I couldn't get back last night as I had to shoot off out. However I think I've sorted it out, I've put a substantial bolt through the work bench and I'm getting continuity using a multimeter. What I want to do is place two pieces of metal flat on the bench to practice butt welding rather than having to clamp the earth cable to one of the pieces. I've tried to send a photo, but I can't do it.

Just clamp the earth to the welding surface. You will know if it works because it will either let you weld or it won't.

I wouldn't pick Ali as a welding surface for general work, maybe if you want to avoid scratching a stainless piece but I use a 10mm thick mild steel plate, welded to the bench frame. I clamp directly to the bench top most of the time