Welding near electronics

[Guldberg]

Forgive me for asking a maybe obvious question, but is there any danger in welding on a stand with an cnc machine on top as long as the power cord is disconnected and the ground as placed as close to the welding as possible?

Im in the proces of build a stand/enclosure for a KX3 and i would like to be able to weld some plates while the machine is on the stand My KX3, tweaks and various stuff

[mc-motorsports]

It's a sketchy, well argued topic. TIG, MIG? High frequency commonly used in the TIG process is a cause for concern.

Just for instance, welding on a fuel injected car.... You have an ECU with delicate electronics, just like your CNC will have, and people weld every day in the engine compartment... I'm leary about TIG welding on a vehicle, again, the HF. I've never had a problem MIG welding though, just disconnect the battery and don't worry. But I have customers who claim they have burned out thier ECU by MIG welding without disconnecting the ECU. It could be they did something like improper grounding, hooked the ground up WAY too far from where they are welding, or used it as an excuse?

One thing though, a lot of times magnetic fields created by welding and HF starts and or backgrounds with TIG welding can damage electronics today, they may not fail until next week. Same goes with static dischage when assembling electronic components.

Is it a good idea? No. I'm sure CNC welders are made with all of these issues in mind, properly grounded, shielded and isolated circuts.

If you have the option, do the welding somewhere else, it's your safest bet.

MC

[ShadeTreeWelder]

It's a sketchy, well argued topic. TIG, MIG? High frequency commonly used in the TIG process is a cause for concern.

Agreed!

However, my experience and I have welding for better than twenty years.
Make sure your machine is well grounded. I have an extra lead in my shop
that is attached to an 8 foot (2.5m) ground rod driven in the ground out side
my shop. Make sure the chassis of the machine, car, truck, etc. is well
grounded prior to welding on the frame or machine. DC welding is of the
least concern the HF of GTAW and PAW (for the units that have that) could
be of concern, but if the unit is well grounded the induced currents from the
HF will not be an issue.

[Guldberg]

Its just MIG welding. ShadeTreeWelder, do you mean ground it as in ground the machine frame to the earthing wire in the wall plug (in absent of a grounding rod)?

I have only two sheets i needed to weld on after the machine was on top. I thing ill just glue them on with some silicone to be on the safe side:-)

[ShadeTreeWelder]

Its just MIG welding. ShadeTreeWelder, do you mean ground it as in ground the machine frame to the earthing wire in the wall plug (in absent of a grounding rod)?

I have only two sheets i needed to weld on after the machine was on top. I thing ill just glue them on with some silicone to be on the safe side:-)

I mean a separate ground (earth) from the machine with the electronics to a
grounding rod. Ideally, and it is code in most parts of the US that each
machine tool have its own ground rod. (just because it is code does not
mean it always happens...)

[harryn]

FWIW, RF travels mostly on the surface of a wire, not in the core.

Basically, it means that wire cross section means nothing in an RF ground.

Use braided cable with lot of surface area for grounding RF.

Sometimes foil can help reduce RF. There is also a very fine copper mesh (almost like cloth) that is good at blocking RF if grounded. I think it is used in a so called "Faraday cage". It does not block the magnetic field, only the RF.