Is there an inverter that will plug into a 12V car cigarette lighter that could be used to power a 110V light duty FCAW or GMAW welder? How about a Makita 4" angle grinder or a 3/8" drill? Just curious.
Thanks,
Rob
Welder? No way.
Drill, grinder yes (as long as you stay under 200W or so).
The cigarette lighter in most cars is fused at 20A IME. DC inverters are inefficient, without looking them up I can’t imagine one that plugs into a cigarette lighter being capable of providing more than 100W or so. That doesn’t leave you enough for the welder, probably not the angle grinder or the drill either, at least not while under load.
How many watts is the welder? Inverters are available in a wide variety of wattages. An inverter that would meet your needs, though, probably can’t be powered through a cigarette lighter…
How about a MillerMatic 140?
From the website:
Input Power
* Requires 1-Phase power
* 115 V, 20 Amps 60Hz
Rated Output
* 90A at 18 VDC, 20% duty cycle
Welding Amperage Range
* 30 - 140 Amps
If not off the lighter, then how about off the battery or something else?
Define “used to power”. For a second? For an hour? There is only so much energy stored in a battery and only so much energy being generated by the alternator when the engine is running.
A car battery will power the starter motor but for a relatively short period of time before it runs down. There is enough stored energy for short bursts (until it recharges) but it will not continue to turn the starter indefinitely.
You might be able to rig the battery to fire the welder for a few seconds but forget it after that.
nm.
Why would the alternator not be more suited to the task than the battery?
2300 watts is quite a bit. You can buy inverters in the 3000 watt range. They’re not cheap. And it would drain the battery in no time if the vehicle is not running.
A stand-alone generator might be a better idea. Or gas welding. Or perhaps this.
Sure, if you want to get a mondo inverter and wire it right to the battery, you can do this. You might want to look at 12v welders - save the expense of an inverter.
Assuming a 100% efficient inverter, 20A at 115 volts translates to a whopping 192 amps through your cigarette lighter. As was noted, the fuse is probably 20 amps, so this ain’t happening.
Batteries brag about cold cranking amps in the 500-800 amp range, so the battery certainly is capable of providing the power needed to weld. Look for a welder that can take 12 volts input, and wire it directly to the battery.
How about a battery powered welder?
You can always go the cheap route
You can also look into an onboard air system to run other tools. If you have enough room under the hood, an old York 210 a/c compressor and a 2.5 gallon air tank can run nearly anything.
The picture in the link shows a kid arc welding with gas goggles, a singlet shirt with no arm coverings. and a glove on one hand. Wow
Heh, I didn’t even look. It was just the first pic of welding with a battery I could find. I guess that’s the extra cheap method.
I started this thread because of the Contractor Special. This was a (IIRC) hybrid diesel pick-up from Dodge that they made as a prototype. One of the features was a set of outlets to power tools. I was thinking that the ability to act as a generator was a cool feature missing from most cars and light trucks, and so I was wondering if there were anything simple that could be done to add this capability up to and including operating a light-duty welder.
Thanks,
Rob
Maybe for welding light bulb filaments? 
I’d second the 12V welder option. Most inverters don’t like reactive loads such as motors or great big welding transformers, and would blow up even if the load is seemingly within spec. This info should be buried in the instruction manual somewhere.
But how long can the battery run a welder before draining? As noted, it’s only got like 15 minutes of running the starter motor, and that’s going to be less power than a welder.
And could the alternator handle the power if you ran it with the engine running?