Large Diameter Cups with Gas Lens and WP-20 torch

[commuter ebikes]

So when I went to frame building school at UBI they used WP-9 torches. They exclusively used #12 cups with a gas lens. They also exclusively used 1/16" electrodes. All of this for welding steel bicycle frames.

I happen to have a WP-20 torch, and I have been using a #8 cup with a gas lens.

When I went to buy a #12 cup, it turned out to be more difficult than I expected because I had to buy a larger gas lens for the larger nozzle.

I found this very handy diagram and chart from https://www.weldingcity.com/tig-weld...s-995795s.html

[commuter ebikes]

So to set up the WP-20 with a #12 cup with gas lens using a 1/16" electrode, I needed:

(1) larger cup gasket PN 54N63-20 (the "20" probably refers to the torch),
(2) 1/16" Large Diameter Gas Lens Collet PN 13N22L,
(3) 1/16" Large Diameter Gas Lens Collet Body PN 45V116S, and
(4) #12 large nozzle PN 57N87.

The first three parts were easy to find. The #12 cup PN 57N87 was seemingly only available from https://weldingdirect.com/tigalno5712.html and they have a minimum order of $25.00.

[commuter ebikes]

And now for something completely different.

Because of that minimum order, I will also set up the WP-20 torch for a #10 cup with gas lens and 3/32" tungsten. Here are those part numbers:

(1) same cup gasket PN 54N63-20,
(2) 3/32" Large Diameter Gas Lens Collet PN 13N23L,
(3) 3/32" Large Diameter Gas Lens Collet Body PN 45V64S, and
(4) #10 large nozzle PN 57N88.

It was the same story here: first three parts widely available with these standardized part numbers, but the #10 cup only available from the place with the $25 minimum order.

[commuter ebikes]

Once again, here are the settings that they use at UBI frame building school for .035"-.045" 4130 Chromoly tubing:

DCEN (of course!), 160A peak, 1.8 pulses per second, 30% on time, 10% background current, 1/16" 1% ceriated tungsten electrode ground to approximately 30 degrees with the tip not blunted, 25 cfh pure Argon, gas lens and #12 cup, .045" ER70S-2 filler material.

The only things that I do differently at home are that I use 2% lanthanated electrodes (I only have 1/16" and 3/32"), and I experiment with the max amperage, PPS, on time, background current, argon flow, filler diameter (still always ER70S-2) and cup size.