Welding with 12 Volt batteries

Take a look here:
Site Link

Rob80

From memory there is an article on LCOOL Site. Not sure of the link, but Google should find it. It is under the Technical info for 90 Series Prado (it might be under others, but haven't looked).

It explained what you need to do, and whatyou need to have for it to work.

Hope this helps !!

RD

I have used two battries for up to 25min of welding. Repaired a broken engine mount on a F250 the first day on the CSR.

I use the + and - off the welder from home and a 300amp jumper lead to link the battries. 2.5 rods work fine (Satin Craft).

A lot of grinding/fileing is required to get good depth of weld.

very very simple mate, two batteries, 1 set jumper leads, U bolt, two hose clamps and a welding rod.
1. line the batteries side by side
2. Clamp U bolt with hose clamps, one to - and the other to + on other battery
3. black lead to free -
4. red lead to free +
5. black lead to chassis, or thing to be welded
6. welding rod clamp into red lead
7. WELD

Thanks guys - fantastic responses and exactly what I needed.
Regards
Rob

We've had to weld up a trailer axle a few years back and a rear control rod on a Prado on the Madigan Line last year.

I carry the welding mask, 2.5mm Satincraft rods, the work lead from my home welder and some jumper leads. In our limited experience, 2 batteries has not been enough. 3 batteries is too much, but was OK if you limited the arc to short bursts. A resistive lead like the fencing wire might be good.

I also carry a hacksaw and a few lengths of flat steel for reinforcing stuff.

Worth practicing at home.

Cheers
phil

Gday,
As for rods-
WIA 12P 2.5mm (GP's) are a great out of position general purpose electrode.
CIG make a rod called a WELDALL and they will do just that (mild steel, cast, high tensile, stailnless nearly anything). Very expensive but well worth it!
If you dont want to fork out for WELDALS see you local boilermaker and see if he'll sell you a hand full of GP's, cast and low hydrogen rods and you can make do.
I usually wrap them up really tight in rags and stuff them in a piece of 50mm PVC( they are no good to you damp or missing the flux).
Cheers

Our club had a night practicing welding last year with different battery setups. Ideally you require 2 heavy duty jumper leads & a couple of short 35mm cu cables with battery terminals. The jumper cable clamps need to be tight on the terminals to avoid arcing which has the potential of blowing up the battery. A hose clamp can be used to hold the leads on more securely. Joining 2 in series (24 volts) can get a 2.5mm rod to run welding up to 3mm steel fairly well. Joining 3 in series (36 volts) will run a 3.2mm rod welding 5 or 6mm thick plate steel without any trouble. We didn't have a DC amp meter to see what we were drawing but volt tests showed minimal drop suggesting a winch under load would flatten the battery far quicker. I carry just the lens out of the welding mask & in the unlikely event it's needed make a cardboard surround. I have a set of welding gloves already for use around the campfire. If the arc is too hot, attatching a short length of fencing wire between one terminal & the jumper lead will allow additional resistance to lower the amperage at the rod but I don't think that would be needed too often particually with 24 volts. In the past we have had success welding a shock absorber eye back on, a spring dropper, a shock absorber mount & cracks in a chassis, in fact in all cases the temparary repairs were so good they remained on after the trip :-)
Cheers Craig.............

Once again my thanks to all above who responded to my query. Excellent practical advice. A great site and a wealth of knowledge out there.

Thanks guys
Rob