[Xtratoy]

I watched a YouTube video from 2014 where the welder was using a Miller stick welder to show some scratch start TIG welding. He showed in the video a foot pedal on off switch he made to terminate weld current and be able to keep gas over cooling weld. Are there any plans available to build one of these? There were a lot if comments on the video about building a similar switch , but I never saw a reply to them.
https://m.youtube.com/watch?v=0h5yw-qrl9c&t=449s

[cj737]

Why not just use a valve back torch and manually open and close it? You then get preflow and postflow completely at your control?

https://www.amazon.com/TIG-Welding-WP-1 ... 9331082149

[MinnesotaDave]

Just base it on the video, it's pretty crude looking but should get it done for you.

Those battery disconnect switches are pretty cheap and you just make the rest to suit you.

[Xtratoy]

I went out in shop and cobbled one together using a couple pieces of wood and a spring clamp. Used a couple parts off of some Air-Arc torches for contact points. Now when you depress the switch, it cuts the welding circuit. cj737, The reason is to terminate the arc without having to pull torch away and loosing gas shielding that protects weld as it solidifies. Mine is pretty crude too, compared to the high tech welders available today. I'll try this before investing a bunch of $$$ in TIG equipment.

[cj737]

I know why you want the ability to extend the gas flow, my point is a manual gas valve does exactly that without you cobbling together a foot pedal that you then drag about. A foot pedal at a bench is great. Moving around and out of position welding its cumbersome.

The gas valve torches allow a pre- and post flow at your discretion.

[BillE.Dee]

I understand the torch head with the gas valve. I understand scratch start. Does moving the torch away far enough to terminate the arc cause a problem with gas coverage or is there still enough coverage (from original valve setting) while the puddle solidifies OR am I really worrying about nuffin.
Bill

[cj737]

I understand the torch head with the gas valve. I understand scratch start. Does moving the torch away far enough to terminate the arc cause a problem with gas coverage or is there still enough coverage (from original valve setting) while the puddle solidifies OR am I really worrying about nuffin.
Bill

Maybe some hygienic stainless would require a long post flow, but if you have 6-10 seconds, in most circumstances you’re fine.

[Poland308]

As long as you don’t have the high frequency turned on then you can snap out and then put it back close enough to maintain coverage.

[cj737]

As long as you don’t have the high frequency turned on then you can snap out and then put it back close enough to maintain coverage.

Wouldn’t be scratch start then...

[MinnesotaDave]

... you can snap out and then put it back close enough to maintain coverage.

That's how I do it too.

[bap_]

I think you're looking for this: https://youtu.be/m2E_PAgoGSE @ 8:56.

Jody shows his version of a scratch start foot petal that allows the operator to not have to snap out and have that split second without shielding. He does this with the stinger connected to the foot pedal (via a contact), and he just discontinues the circuit when he lifts up on the pedal, and uses a valve torch for manual shielding.