Will TIG noise be a problem?

I'm building a simple welding positioner (like a Lazy Susan) and it will be driven by an Arduino-controlled stepper. The final unit will be housed in a steel box and rotation is controlled by a foot-switch.

Just wondering if the electronic noise generated by the TIG welding process may upset the Arduino. The end-user will be about 90 miles from me so I can't do any early testing.

If so - any tips on noise filtering would be a big help.

=Alan R.

You should assume that noise will be a serious problem and design everything accordingly. This would include putting all electronics into a well grounded conductive housing and placing noise-reducing feedthroughs on all wires entering the box (including the AC power supply). Also, the power supply for the stepper motor must be very well decoupled from the Arduino power supply. Usually heavy duty ground strap braid is used to make sure all metal components are electrically connected -- the turntable bearings are probably not conductive.

Thanks - will proceed accordingly...

Can't offer and answer to the question but have you considered the TIG aspect of the problem.
How do you plan to connect the TIG welding ground lead to the lazy susie plinth-plate. If you connect to the static bearing housing their balls will literally burn up. You will need some sort of sliding brush contact that electrically connects directly to the table shaft or the table plinth-plate. Also bear in mind that the weld current will probably be in the range of 20 to 200 amps so the ground lead/contact system will need to be substantial.

jackrae:
How do you plan to connect the TIG welding ground lead to the lazy susie plinth-plate. If you connect to the static bearing housing their balls will literally burn up. You will need some sort of sliding brush contact that electrically connects directly to the table shaft or the table plinth-plate.

http://weldingweb.com/showthread.php?28578-Welding-Positioner-In-Kit-Form&p=261960#post261960
http://weldingweb.com/showthread.php?28578-Welding-Positioner-In-Kit-Form&p=278859#post278859

They must be using some kind of tinned copper braid.

My client is def aware of the ground current issues. This is a mostly purpose-built unit for welding flanges to pipes - biggest is about 8" dia. There is a 1" steel shaft going thru a bronze sleeve bearing (for horizontal stabilization), and the shaft is sitting on a roller thrust bearing. They may not use a sliding ground connection - but if they do it can be connected near the top of the shaft and no current will flow thru the lower bearings. Also this is a simple enough operation that the work-piece could be grounded directly. In one revolution the ground lead would not become tangled.

I'm more worried about the radiated RF energy that may interfere with the Arduino.

=A.

I have a lot more experience in welding than electronics, but I'll comment based on experience in the field.
If the TIG unit in question has HF (high frequency) start, or you are welding in AC with continuous HF then there CAN be lots of issues for any connected electronic devices.
This will escpecially be the case on older units which use points for the HF.
Proper grounding and shielding is a must!
Seen many a clamp meter die on AC/HF TIG units, but can't say I've seen a commercial positioner have major problems.
The earthing issue is separate. You either need a carbon brush & slip ring, or simply attach a rotating earth to the pipe.
The latter would be easier for you, but a bit more work for them.
Given the low cost of commercial positioners you'd be hard pressed to build one economically unless you are introducing sequencing or other electronic controls not normally found on low cost units.