arc welding on a vehicle

[skylarkguy]

Hi folks,

I'm pretty new to welding. I picked up a used Miller thunderbolt AC/DC machine. It seems to work OK and I have been practicing some...it's coming along. My question is this.

I want to attach some D-rings or hooks to my Frankenstein dump truck (84 Chevy) besides disconnecting the battery what else should I be concerned with when welding to a vehicle?

Thanks

 

[Haywire]

Be aware of where your vehicle wiring is running. I bought a car once that had some welding done on it and the wire run behind the panel they were welding on melted.

Ian

 

[Joe H]

The alternator too.

Joe H

 

[Craig Clayton]

I would suggest that you keep the ground ( the other lead ) as close as possible. I even clean the local area for the ground to make the best possible contact.
The reason being current could flow bearings and harm them.

Craig Clayton

 

[N7943h]

Welding to the frame will weaken it from the heat which is why you see items bolted or riveted to frame members. Just pulling the ground wire off the battery will protect the electrical.

 

[Canada_CT230]

In our old shop we used to just disconnect the battery terminal at first. That will protect the onboard computers. Alternately you can buy a welding gizmo that you hook to the battery and it protects the system too. We got one of those cause it was faster but for once or twice you'd be stupid to buy one.

Agreed about knowing whats nearby (think heat) and frame weakening! Electricity takes the shortest route so the ground clamp should not be on the front bumper when welding at the back.

 

[yomax4]

May not need to but I always Double Ground.

 

[sjb]

So how is disconnecting the battery going to protect anything? If you induce a voltage spike in to the wiring I would expect the battery to absorb a lot of it. It should provide a low impedance path for anything above the battery voltage. I can see how a surge suppressor across the battery could help.

As already mentioned you need to pay attention to the path from the welding rod to the ground clamp.

Stan

 

[Canada_CT230]

Go ahead and weld on a vehicle w/o disconnecting then. All those mechanics/welders probably don't know what they are doing anyway. An ECM for your car would probably only run a couple thousand dollars. Try & maybe fry???

 

[Canada_CT230]

So how is disconnecting the battery going to protect anything? If you induce a voltage spike in to the wiring I would expect the battery to absorb a lot of it. It should provide a low impedance path for anything above the battery voltage. I can see how a surge suppressor across the battery could help.

As already mentioned you need to pay attention to the path from the welding rod to the ground clamp.

Stan

Cause when u disconnect you remove the electric wiring from the frame (ground) of the vehicle. Therefore there is NO voltage going down the wiring. When u leave stuff connected it completes the loop.