[admin]

I have never worked a job where pulsing with the pedal was even allowed except for job shop work... but it seems that hot rod fabricators pump the pedal a lot. Since bump welding with a torch switch is done on anodized aluminum tubing, I guess its worth a look.
Also, just messing around trying to learn something.

Jody
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[ncologerojr]

I like to manually pump the pedal sometimes, it's something I also noticed while watching hot rod/motorcycle guys work. It seems to be a bit of a controversial technique. Here is a cool older video of Bryan Fuller and Mark Prosser welding a chromoly "T" joint. The cool part is that Bryan pumps the pedal while welding, and then they test the joint strength after.

http://youtu.be/pYuaHzCY3G0

[Louie1961]

The guy who taught me how to TIG weld recommended pumping the pedal at the end of the weld as a means of minimizing the crater (along with simultaneously swirling the torch around in a small circle). Other than that, I have not seen it done. Then again, my experiences are limited, so take it with a grain of salt.

[Superiorwelding]

Great vid and weld Jody.

I don't necessarily pump the pedal a lot like Jody showed but I think we all do it on occasion. To be honest, I was never all that consistant by using this method and I guess I never practiced it very much. For me I hardly have the application where I need pulse. Most of the time it is full amperage, at least what I set it to. Might have to sit down and give this more practice.
-Jonathan

[Otto Nobedder]

While I modulate the pedal in most situations, I can't say I "pump" it except in aluminum work.

This is most often in repair work on dirty aluminum, and serves the same purpose as the torch switch TamJeff uses in anodized aluminum.

I also do it with bad fits on new aluminum, for filling gaps, as it gives me the control to advance a bit at a time and see each advance clearly while freezing it quickly.

I don't recall using large pedal pulses more than occasionally on steels.

Steve S

[weldin mike 27]

Also, would a pedal have too much travel to be efficient? Micro switch on.off.on.off. pedal onnnn.offfff.onnnnn.offfff. never used one so dont know.

[MinnesotaDave]

Based on the video, I figure my Airco must have a range of about 0.5 to 2.0 pulses per sec.

...and a variable adjustable background current...

Not bad for 1963 - Always knew it was more modern than people think

[weldingt]

I have used it in the past for visual appearance but it was also helpful when I had to qualify on 1/2" and 1" Socket Welds in the Navy. The interpass temp was in the 250 deg F range and "pulsing" the pedal would help the test assembly stay cooler.

If the NiCu got too hot, it was easy to get incomplete penetration at the root. So I would set the max amperage to the max on the WPS and then pulse every 1/32" or so.

For some reason these gave me a hard time . We had pulse capabilities on the Syncrowaves in the shop and the shipyards had WPS's for using pulsed GTAW on NIcu and Cuni socket welds but we (active duty USN) only had certain procedures we could use.