TIG Welding on a completed robot

After running in a couple of competitions and some hard hits, we noticed that a couple of our aluminum welds have hairline cracks. We would like to repair them but are nervous about the potential impact of welding around the electronics on the bot. It would be much easier if we repaired the welds without removing all the components from the bot. We would obviously protect the electronics from the heat associated with welding, but are wondering if there is a risk of any other damage to sensitive components (eg. SparkMax, Roborio, PDH, etc). Should we be concerned?

As an aside, in the past we have had the experience of having some encoders mysteriously stop working following welding on a bot, thus we are being a little extra cautious about this.

Speaking generally…

TIG arc starts are high frequency and high voltage. They can be 2,000-10,000V and are notorious for killing all sorts of electronics. I would not want to weld with a HF start anywhere near FRC electronics.

The electronics have a much higher chance of surviving if you can disable the HF start function and do a lift-arc start (sometimes called scratch start). Actual welding usually runs a 16-38V kind of range with pure argon shielding gas (helium or helium mixes can be a little lower) and runs a lower risk of breaking down any isolation components present on attached electrical devices than the thousands of volts present in HF/HV starters.

I see your choices as:

  1. Run HF/HV start, get a clean weld, highest risk to electronics
  2. Lift-arc start, potentially dirtier welds, lower risk to electronics
  3. Torch braze the joints, high skill, lower strength, no risk to electronics
  4. Remove parts and weld with HF/HV, best weld quality, no risk to electronics, most labor time (by the sounds of it)

Don’t forget to do stop-drills past the end of the cracks and gouge the cracks that you can for a stronger repair!


@JamesCH95 has it right, you are taking a serious risk if you TIG weld around your electronics. Your best solution, even though it will consume more time, is to remove to components and weld them away from any electronic components.

I would avoid it altogether if possible. My suggestion would be to make brackets/gussets and attach them with rivets/bolts by match drilling, this would be over top of the weakened joints. That involves the least amount of disassembly possible, no risk to electronics, no risk of further warping your frame due to heat, and will be pretty dang strong.

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