on the way outta the cleanup with met up with some guys with a broken steering arm and all of us got together and proceeeded to throw down 3 battteries in series for a trail fix. after welding for about ~(laid like 7-8 puddles max)2 minutes the one of the batteries violently(shotgun, 3030 shot caliper) blew off the covers on the fill holes???

was this just a quick buildup of hydrogen gas that the cap couldnt vent off?? we all got covered with a light spray of sulfuric acid that wasnt very pleasant and luckily didnt get into anyones eyes...any pointers, ideas, safety tips:D

I thought the typical way of doing it was 2 batteries and a couple jumper cables, why three?

2 isnt enough power a lot of times. Next time you weld with batteries. Put blankets over them. It's not uncommon for them to blow

I think the battery that exploded was probably in bad shape (sulfated), and overheated when subjected to a high current demand.

Here's some info:

http://www.interstatebatteries.com/www_2001/content/warranty/plain_24.htm

I'd only use batteries to weld in an emergency, and then maybe cover them with an old tarp or something.

Why not build an onboard welder. Try here:

http://www.pirate4x4.com/tech/on-boardwelder/index.html

Or Here:

http://www.huv.com/jon/jeep/Welder/on-board-welder.html

Were you close enough to the battery, that the sparks from welding could have ignited the hydrogen gas escaping from the battery?

I have had one battery blow up right in my face. Singed my eyebrows, and the hair on the front of my head. I thought I was going to be deaf from it, my hearing eventually came back, though I am sure that It must have done some dammage. I was really luck that my head wasn't about 6" more into the engine compartment. The flames that shot straight up were so hot that they burned clear through about 1/4" of underhood insulation in just the split second that the flames flashed up. My face would have been toasted if it had been in that path.

This happened in the woods, about a 30 min. walk from anywhere, working on a friends car who I was with. After some hiking we cam back to find the car wouldn't start. I checked the battery connections and they were a little corroded. I was able to remove the cables from the battery by hand with some work(he had no tools in his car) I asked him if he had anything to clean off the terminals with, and he brings me a Flat Bastard ;) That just happened to be in his car. I cleaned up the contact areas as good as possible, and went to connect the cables back up. They did not want to go back on, so I just gave them little taps with the file ,a dn that worked. Got the neg. on, and started on the pos. when BOOM :nuke: . Knocked me back a few feet. Scared the CRAP out of me. I was very confused, and couldn't hear anything but RING for about 20 min. My hearing came back to normal over the next 3 to 4 days.

There must have been a very small spark from the file that ignited the hydrogen escaping fromt he battery from trying to start it earler.

Looking back.... I am very lucky something worse didn't happen.


Sean

Sealed batteries are much safer.

Three things.

1) Hydrogen gas is explosive so keep the batteries away from the welding sparcs.

2) Three batteries are too much voltage for almost all 1/8" elecrodes except maybe 7024 (thick flux "drag" rod). Use 2 in series with the right welding rod. Rod suggestions are 1/8" 6011 or 6013.

3) Add some resistance to give the voltage some "droop" (i.e. current limit). I tried a 1/4" steel rod about three feet long and clamped on at different lengths. It gets hot but gives a little control.

The concept is old but useable. Before cheap welders were available, manufacturers used huge 40 to 60 kilowatt voltage source supplies and a bunch of MOGs (multiple operator grid) for control which were just adjustable resistors.

I was a design engineer for Miller Electric (big blue) for 15 years so I not pulling this out of my _ss.

Watch those fumes though.

Paul,
Glad to see ya all made it out ok and not get burned up with the acid and stuff...

Originally posted by Chris Geiger
Sealed batteries are much safer.

There is no such thing as a "sealed" automotive battery. Even a maintenance free and a gell filled battery have vents. Either one could still explode if they get hot enough.


If one of the batteries was sulfated it could easly cause it to explode under heavy current draw.

hey booga, First ovall, a 3030 aint no shotgun. yea, captain birfield was quiet a dumbass. we gots to go wheelin again, ill send ya pics of the top im makin.
PAt

I usually leave them in the vehicle with the hood shut, but that was before a buddy of mine put in an onboard welder. Now it ain't no thing. :flipoff2: Allways make sure you cover the batteries though. Acid aint no joke!

JOe

Glad no one was hurt!Every time we have had to pull this fix we would start with 2 batterys but end up adding the 3ed every time.This has been with 6013 rod.We usually trough a tarp over them.

great info fellas, thanks a lot. guess well have to cover them with 3 pair of fat pats undies next time:flipoff2: :flipoff2:

Originally posted by YotaCrawler
hey booga, First ovall, a 3030 aint no shotgun. yea, captain birfield was quiet a dumbass. we gots to go wheelin again, ill send ya pics of the top im makin.
PAt

as loud as a shotgun, COMA, 3030:flipoff2:

i wanna see the top!:D

captain COOKIE speaking, I still dont want to barrow pants from you!!!!!!! you said 3030 caliber you,you,you fawkin fawk fawk?!?1?!?!?!?:flipoff2: when ya comin up again?
PAt