Can you run a welder of a 12v to 240v inverter? Just need a small MMA type piece of kit to carry around when out and about. As experienced this weekend at Kirton, a welder can be a valuable bit of kit to carry!

If its not possible what are the options..........Needs to be portable and not too £££! MMA based no gas...

Cheers to John (KingCJ Kirton Marshal) for the use of his kit to weld my mates control arm mount back onto his chassis.

Cheers

You can do it a lot cheaper...

You will need two or preferably three car batteries. Connect them in series, ie 24V or better 36Volts.

Use two long jumper cables as welding cables. Use one as earth clamp and the other to hold the welding rod.

REMEMBER TO USE ADEQUATE EYE PROTECTION!

Polarity: Normally when welding from batteries you will connect the negative terminal to the welding rod and the positive terminal to the earth clamp. This will vary with the welding rods used.

MAKE SURE THE BATTERIES DO NOT HAVE ELECTRIC CONNECTION WITH CAR WELDED ON!

A cheap little welder using gasless flux wire can be converted to be used direct from the batteries if you prefer MIG/MAG welding above welding with rods.



Edited to add:

Or you could use an extra alternator solely for welding purposes. Bypass the regulator and feed a (preferably controllable) amount of the generated voltage back into the field windings. A modern alternator wil be able to produce about 100 volt at 90amp. Not all that many amp for welding, but it is high frequency AC which has greater penetration abilities than normal welding current. You'll soon learn to enjoy the very special high-pitch humming high frequency AC welding gives...

DONT LET THE CURRENT FROM THIS SETUP CONTACT ANY HUMANS! The voltage produced could be dangerrous!

Cheers Kim,

The makeshift car battery way would be a last resort. I would prefer a MAG set-up and a single phase unit run of an inverter sounds like a good option, if possible?

There is no reason it cant work, its just a waste of electric energy. Either you weld straigt from the batteries or transform 12volt DC to 120 (or 220) volts AC and then back to 24 volts DC in the welder the energy will still be provided form the batteries. Each time you transform the volttage up or down you loose about 10-15 % due to heat.

If you want a mag unit then buy some cheap mag welder, rip out the transformer, plug in an anderson connector and make a couple of jump leads with anderson connectors in them. That way you still have the MIG/MAG ability, but without loosing energy into transforming the voltage twice. You will have longer welding time from the same batteries.

If you really want to make you car a mobile welding station, then get a 24 volt alternator and two spare batteries. Connect the batteries in series, and connect to the 24V alternator. If you are welding on another car than you own the alternator can be left running and charge the batteries while you are welding. The alternator will not be harmed by this.