Plasma Cutting on a Truck (1 Viewer)

[41magsnub]

Since there are no stupid questions...

I need to cut the frame a bit on my 80 series for the 4x4 labs bumper build. I have multiple tools that can do the job, the coolest of them is the plasma cutter.

If I use that, standard burning holes in metal safety precautions and making sure any wiring is well away from the cutting area aside, do I need to worry about the current frying the electronics on the rig?

Same question for welding!

 

[Pin_Head]

It depends on the type of torch. If the torch needs to be in contact with the metal to start the arc, then this may not be good for the electronics because of the high voltage HF pulse used to start the torch. If you have a pilot arc type torch, where the arc is started before you contact the metal, it should be no problem.

For welding, you don't want to use TIG units that use HF starting.

 

[41magsnub]

I actually don't know which way the plasma cutter starts... I'll have to test that. It is a Hypertherm powermax 30.

The welding process is MIG.

 

[fieldsken1]

just undo the battery

 

[Ebag333]

Know of one person in the 80's forum who is convinced he fried his ECU by welding on the truck.

Why risk it? As mentioned before just disconnect the battery.

 

[41magsnub]

That's what I'll do then. I was definitely planning to disconnect the battery, but was concerned that that would not be good enough.

 

[Pin_Head]

It may not be good enough for HF, like on plasma cutters and TIG welding. HF is high frequency radiation and can be picked up by any wire acting as an antenna. MIG and stick welding don't use HF pulses to start the arc.

 

[41magsnub]

It may not be good enough for HF, like on plasma cutters and TIG welding. HF is high frequency radiation and can be picked up by any wire acting as an antenna. MIG and stick welding don't use HF pulses to start the arc.

I'm wussing out on the plasma cutter. Should have mentioned that! Going back to the sawzall. I was referring to the MIG welding portion where I tack the parts together on the truck.

 

[Pin_Head]

No problem. You probably don't even need to disconnect the battery, but it is easy. There are thousands of welding trucks out there working every day with stick and MIG and nobody disconnects the ground cable on them. HF is a different thing.

 

[RHINO]

its ok, a good habit to get into is keeping the ground clamp close to your work and moving it with you when you switch to the other frame rail.

 

[prado t]

Or a ground strap, but undoing the battery is cheaper.

I know a guy who was doing some welding work to his Walking Floor chip trailer. The peterbilt tractor was connected to the trailer. The guy went to start the truck to activate the PTO. .............. The N14 cummins $ 6000.00 ECU was fried. The guy did not use a ground strap or disconnect the batteries. An Isolated case ; NOT. and this was done using a 140 AMP welder.


Always diconnect the battery or use a ground strap

 

[41magsnub]

We ended up using the plasma cutter (with the battery disconnected). It did start away from the work area so I went for it. Truck starts up and all the doodads work fine. The ground clamp was never more than about 4" from the cut.

 

[JohnR]

Keep the clamp real close, and disconnect the battery. I've HF tig welded on countless vehicles, as long as you keep the ground close by, you're good to go.

 

[Spook50]

It may not be good enough for HF, like on plasma cutters and TIG welding. HF is high frequency radiation and can be picked up by any wire acting as an antenna. MIG and stick welding don't use HF pulses to start the arc.

Exactly why, even for MIG, I disconnect and completely remove any sensitive electronics on my truck and set it all on the bench. Amp, stereo, ECU, ignition box, etc. Probably overkill with the safety aspect, but that crap's expensive and a bitch to troubleshoot.