Tig welding tips, questions, equipment, applications, instructions, techniques, tig welding machines, troubleshooting tig welding process
nelson
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My jobs are mostly small. I plan and prepare, then switch on/gas on.

Lately I don't do too much prep, going for fast and strong, not pretty.

Do you guys kick the pedal once at first just to purge the torch cable without welding? Sounds logical but I've never heard of it.

Thanks!
Stone knives and bearskins.....and a NEW EVERLAST 164SI !!!
That's my newly shared work welder.
At home I got a Power Tig 185 DV. Nice, but no plasma cutting... Nice tight arc after a second.
Farmwelding
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nelson wrote:My jobs are mostly small. I plan and prepare, then switch on/gas on.

Lately I don't do too much prep, going for fast and strong, not pretty.

Do you guys kick the pedal once at first just to purge the torch cable without welding? Sounds logical but I've never heard of it.

Thanks!
Sometime I do but I don't do a while lot of critical work that would require a pre flow. Although I believe the machine I use has a pre set 1 or 2 second pre flow any way. A lot of newer machines have pre flow settings as well.
A student now but really want to weld everyday. Want to learn everything about everything. Want to become a knower of all and master of none.
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Nick
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Adjusting for a longer pre-flow accomplishes just that. On a 12.5ft gas hose, 0.4s usually enough, but on a 25ft hose, I prefer to use 0.6-0.8s.
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noddybrian
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    Thu Jan 24, 2013 12:13 pm

Always do it as most of the machines I use don't have auto preflow - majority of Chinese machines seen here don't have preflow either - mate just bought an interesting one cheap - not had a chance to try it but it looks like they are really putting some effort into R&D - will hopefully get a chance to play & report back.
nelson
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Yeah, I have one of those (relatively) cheap ones...no preflow. Odd that I've never seen this mentioned, with all the shining welding I've seen here. I plan to start doing it regularly. Will it hurt the spark gap, etc?
Stone knives and bearskins.....and a NEW EVERLAST 164SI !!!
That's my newly shared work welder.
At home I got a Power Tig 185 DV. Nice, but no plasma cutting... Nice tight arc after a second.
noddybrian
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    Thu Jan 24, 2013 12:13 pm

It has been mentioned but not often - I believe Jody mentioned it when testing that nasty AHP thing - they seem to listen to feedback so maybe next years model will have preflow ! - don't think dry firing a Tig will hurt anything but some don't like firing the HF on the next start so you have to momentarily earth the electrode without power to discharge residual volts first.
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I do this.

Syncrowave 250DX.

I tap the pedal for a pre-flow, then drop my hood and arc off.

Not for the pre-flow benefit, but because if the pre-flow is established, I have a stable arc immediately, where it may wander a bit if I just drop my hood and "pedal down".

Steve S
Poland308
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I have a 25 ft hose and a 50 ft. I have a pre flow of 1 second. It works well with both and it's not a terrible lag on the arc start.
I have more questions than answers

Josh
cj737
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    Thu Sep 29, 2016 8:59 am

I tap the pedal before I drop the hood to insure I have the gas ON when I strike my first arc. Then I know I have gas flowing to the part, the line is fully pressurized, and I can confirm the flow to my cheek.

On stainless especially, I pre-flow manually for several seconds to purge the area, then while flowing over the part, arc up, weld, then post flow. And post flow manually again. For me, it produces much better welds. You don't need to spark to get the gas flowing, simply turn the cup away and bump the pedal. The solenoid should fire and allow the gas to run.
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