4WD BATTERY-POWERED WELDER
Here’s a brilliant, albeit last-resort, option for a DIY welder using your 4WD’s batteries. The idea is pretty simple but some welding experience is definitely an advantage and safety is absolutely paramount. If in doubt, don’t attempt it.
1. Start by hooking two to three batteries up in series. That means linking the positive terminal of one battery to the negative terminal on the next battery using a jumper lead cable (or similar).
2. Continue the same procedure if adding a third battery but, remember, you’ve now got 24-36V, which is nothing to sneeze at.
3. Next, run a separate jumper lead from the unoccupied positive terminal of the battery to the metal you’re about to weld.
4. Before connecting the negative battery terminal up, you’re better off setting up your welding rod so no accidental contact is made. You’ll need to secure the welding rod to the jumper lead clamp nice and tight, so you can either use a pair of vice grips or file out a groove for the welding stick to sit in nice and snug.
5. Then it’s as simple as connecting the jumper lead to the negative terminal on the battery and starting the weld. It’s also a very good idea to throw a protective cover (fire blanket, etc.) over the bank of batteries to prevent sparks igniting the fumes from your batteries and help provide some protection if they were to explode.
Controlling the current: If the current is too high, you could introduce some resistance in the circuit by replacing one of the cable links between the batteries with a smaller diameter cable – even fencing wire will do. But be warned, it will heat up very quickly, and could melt in an instant, so keep a close eye on it!
Can I spare the rod? Although a few spare silver coins have been known to get the job done (roughly), it’s illegal to destroy currency. You’re probably better off using 1/8in (6011) welding rods, which work best for this voltage and current.
REMEMBER, SAFETY FIRST:
• Overheating the batteries could cause them to explode. Any bulging, a strong chemical smell or heat can be an indication.
• One battery alone will not supply the power required for this technique.
• All batteries should be fully charged and rated at 700 CCA or above.
• This method will discharge the batteries within a few minutes of continuous use, so make it count!
• Always carry and use safety gear (gloves and welding mask at a minimum).