Another odball question. What I'm good at

[handirifle]

I was reading an ATV magazine the other day, about welder for "in the field" repairs. There were about 6 models. One of three of them was just two batteries (usually 2 gell cell) wired in series to produce 24V. The next was the same setup, but with a charger, so it could be kept plugged into the wall for theoretical unlimited power supply (not power output), and the third was a 150 amp alternator, with a control panel that is mounted into the vehicle. The third (of these three) was the most expensive at around $600.

Number two, is the most intriguing to me. I know one would have about the same $$$ in it as a used or new Lincoln buzz box, but would have the added benifit of portability, and field use where remote repairs were needed and no power was available.

Has anyone used anything like this before?

I realize it would lack power output controls, but is there some other way to accomplish this, so you wouldn't say, burn through the 1/8" metal you might need to repair?

I realize also, there is a limit to portable power (ie dead batteries) and it would not be a production use type of thing. How practical are these?

 

[Pete Judd]

Years ago, I welded in a pinch a cast iron marine manifold with a pair of jumper cables to a the 12V battery, and a coat hanger. It can be done in a pinch, and it stopped the leak and got us back to port.

 

[yomax4]

I was reading an ATV magazine the other day, about welder for "in the field" repairs. There were about 6 models. One of three of them was just two batteries (usually 2 gell cell) wired in series to produce 24V. The next was the same setup, but with a charger, so it could be kept plugged into the wall for theoretical unlimited power supply (not power output), and the third was a 150 amp alternator, with a control panel that is mounted into the vehicle. The third (of these three) was the most expensive at around $600.

Number two, is the most intriguing to me. I know one would have about the same $$$ in it as a used or new Lincoln buzz box, but would have the added benifit of portability, and field use where remote repairs were needed and no power was available.

Has anyone used anything like this before?
I realize it would lack power output controls, but is there some other way to accomplish this, so you wouldn't say, burn through the 1/8" metal you might need to repair?

I realize also, there is a limit to portable power (ie dead batteries) and it would not be a production use type of thing. How practical are these?

Most of the welders you describe were in the form of a spool gun. They had no voltage control but you could control output by using the wire speed. Faster on thin material, Slower on thicker material. Add argon and you could repair aluminum in the field. The ones I have used hooked to a running car or truck battery. These units really never caught on and I have not seen one for years. Back in the day, They were $500 and not all that durable. You had many options in the $500 range so most folks bought something else that could be used all day in the shop.

 

[rankrank1]

There are actually two very nicely put together videos on Youtube showing how to do emergency repairs with 3 (12 volt) car battieries and 1/8" arc welding rod. Hooking the 3 batteries up is series produces over 36 volts for an arc voltage which is getting somewhat closer to a real welders arc voltage. Yes it is possible to weld with less than 36 volt arc voltage, but you have to be really good to keep the rod from sticking all the time with low voltages.

The Youtube video is targeted towards the Jeep offroad type enthusiast and there are actually two videos. One is the actual field repair being done, but does not really show the welder hook-up details. The second video was made as a response to the first video and shows the full detailed improvised welder set-up laid out on the garage floor and explains how to do everything safely and then a demo weld is performed with the emergency system.

 

[handirifle]

Most of the welders you describe were in the form of a spool gun. They had no voltage control but you could control output by using the wire speed. Faster on thin material, Slower on thicker material. Add argon and you could repair aluminum in the field. The ones I have used hooked to a running car or truck battery. These units really never caught on and I have not seen one for years. Back in the day, They were $500 and not all that durable. You had many options in the $500 range so most folks bought something else that could be used all day in the shop.

Actually the article described 6 or so, and about half were stick and the other half were spool. I did read an article about one of them about 4 years back, and it was for a single battery, with a spool gun.

Another one the guy went into great detail to describe the jittery puddle of the high intensity 12V arc, and that it jiggled the impurities to the surface, but he did mention it was tricky to control.

Some of these units, listed were close to $1,000, not sure why but theats what the article listed for MSRP.

There was one that was mearly cables to a battery, for stick welding, and they did mention they nearly ruined the battery posts with the clamp on style hook ups.

Thanks for the feedback, looks like they're best left to pure emergency.

 

[rankrank1]

Here is a link to the Youtube video I was describing in my previous post. It is a pretty good tuturial on how to do field emergency type repairs with 3 car batteries - even shows volt meter readings before and after welding. My guess is this would not hurt the batteries at all.

Only thing I can add that is not covered in this video is that I would definitely use one of quick release spring loaded type stingers so that I could quickly break the circuit if I happened to stick the rod while welding. I think this would be good insurance for protecting the batteries against a prolonged short circuit if a rod is stuck. I think a cheap quick release stinger is like $2.99 at Harbor Freight and almost everyone uses the spring release type of stingers anyway (as compared to the screw down clamping locking type stingers so it was not mentioned).

YouTube - Arc Welding with 3 Car Batteries (Tutorial & Demo)

 

[jayste]

Years ago, I welded in a pinch a cast iron marine manifold with a pair of jumper cables to a the 12V battery, and a coat hanger. It can be done in a pinch, and it stopped the leak and got us back to port.

Nice!:thumbsup:

 

[chopped]

Great video ,thanks for sharing i am curious how four batteries would go. He had good penitration but wonder if the fourth one would add the oompf to give a smoother weld?

 

[rankrank1]

Great video ,thanks for sharing i am curious how four batteries would go. He had good penitration but wonder if the fourth one would add the oompf to give a smoother weld?

I am not sure adding a 4th battery would necessarily be a good idea. If more oompf is needed it might be a better idea to switch the polarity to electrode + and ground - which should provide more penetration as compared to having it electrode - and ground + like this diagram. That said, the trade-off may be that the arc will probably get harsher and less smooth if you switch the polarities for more penetration on this particular improvised set-up.

The 2nd reason I do not think I would add a 4th battery is that in general arc welding with SMAW is not designed to be done with high voltage and low amps, instead SMAW rods are designed to be used with low voltage and higher amps. From what little I have read it seems that the sweet spot for actual welding is somwewhere around 30 volts or less for when welding is happening. Of course many real welders have higher open circuit voltages than this which do help you get the arc started easier, but somehow the weld voltage is somehow reduced closer to 30 volts at the weld point as welding starts happening. I do not know if there is special circuitry inside a real welder controlling this redecution or if it is all simply contolled by arc gap that the person maintains with the stinger when welding (most introductory welding books state the arc voltage goes up to a point with too much arc gap and down to a point with too little arc gap so arc gap is at least a partial factor).

Ideally it may be that 3 batteries, consisting of two 12 volts batteries and one 6 volt battery all connected in series for 30 volts total, might provide the optimum in smooth weld capability on an improvised welder such as this as that would be closer to SMAW rod target of somwehere around 30 volts. That said only users with an old antique tractor/car are likely to have a 6 volt battery lying around so I doubt that anyone has ever tried it. Still, I thought the video maker did a pretty decent job with his three 12 volt battery method as he is at least somewhat close to the 30 volt ideal target and the little extra he is over in voltage does help his OCV and does help his initial arc strike happen.