MIG welding on machinery

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MIG welding on machinery

Post by torchmd » Sun Jul 27, 2014 12:23 pm

I have to do some repairs on the metal base of a mini mill with dro. Will careful grounding be enough to protect the electronics,,motor and dro? Or should I spend the time disassembling it all. I hate the idea of spending four hours taking those thing apart, and back together again, but it hate the idea of replacing it all more

Thank you!

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Re: MIG welding on machinery

Post by Russ Hanscom » Sun Jul 27, 2014 1:47 pm

In theory, careful grounding should work, but...

I would suggest removing or disconnecting the electronics. If the scales are the magnetic type, probably should remove them too.

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Re: MIG welding on machinery

Post by hammermill » Sun Jul 27, 2014 2:07 pm

I will add keep the ground point as close to the weld as possible. And cables as far Way as you can. And unplug everything g. Don't need ground loops cooking stuff.

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Re: MIG welding on machinery

Post by redneckalbertan » Sun Jul 27, 2014 3:09 pm

I agree with the sentiments expressed above, at a minimum I would unplug the devices and choose the ground points carefully. I don't know how the electromagnetic fields generated from welding will interact with magnetic scales. It may be wise to remove the scales.

In theory welding on a truck frame with the negative terminals of the batteries disconnected saves the computers in the truck. Or welding with ground close to where you are welding should prevent damage to the computer. Earlier this year I was welding on an tilting sub frame bolted to a truck that should not have given me a ground loop to the computer with my ground as close as practically possible to my weld point with the negative terminals of the batteries disconnected and I still allegedly did damage to the computer... So use caution.

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Re: MIG welding on machinery

Post by steamin10 » Mon Aug 04, 2014 9:43 am

In my experience, I cannot control the EMF, and eddy currents associated with welding around computers. Computers live on very low voltages for their periferals, and EMF can cause problems, let alone wild ground voltages.

I always isolate by removing fusing or batteries from a project, so the circuits are DEAD. Any kind of computer circuit within 3-4 feet are removed. So far it works having lost a control panel on a Ford Ranger that had some welding. The meters and controls failed to function after some frame mounts were replaced.

Nuff said.
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Re: MIG welding on machinery

Post by warmstrong1955 » Mon Aug 04, 2014 10:12 am

When the first 60 series DDEC (Detroit Diesel Electronic Control) engines came out, they insisted that the ECM should be completely unplugged prior to any welding anywhere on the machine.
I forget when they made the change, second or third generation, but they changed the procedure to simply disconnecting the batteries, which was something we always did anyway.

Some electronically engines still require the ECM's to be unplugged, some don't. Hard to keep track......so....when in doubt, at least unplug it! Still not sure, and the manufacturer can't tell you.... I'm with Steamin....yard the thing out and haul it to the kitchen table before you strike an arc.

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Re: MIG welding on machinery

Post by GeorgeGaskill » Wed Dec 03, 2014 7:06 pm

Parallel circuits are almost impossible to eliminate and since solid state gear has such low reverse voltages in most cases, they should be completely removed. Otherwise, oxy/acetylene.

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