[Negativentropy]

What the hell am I doing wrong? These stubby gas lenses with pyrex cups dont work at all.

https://www.youtube.com/watch?v=evtjPbkEJow

Its like there is zero gas going through, but when I test them for leaks and gas flow there doesnt seem to be anything wrong.

Cant figure it out! I feel like im either missing something really obvious or there is some little detail I dont understand.

[cj737]

Two things that comes to mind: different gas lenses use different insulators. So verify that the insulator you are using is compatible with the lens.

Its hard to determine from your vid, but both tungstens appear to be suffering from too low a CFH. Your tungsten should not be discoloring that heavily that quickly.

A poor fit and low CFH will cause these problems in any manufacturer's lenses. But its also quite possible that the ones you both are cheap and just suck? Some details about the setup and brand would help-

[Just Nick]

Are those the cheap amazon gas lens kits ? If so log onto Welding tips and Tricks store and buy a stubby gas lens kit for Jody made by CK Worldwide

[pgk]

Defiantly a gas coverage problem, have you tried turning up your cfm on your regulator while using that setup?

[Oscar]

Going by the way my gas lens kits are setup...

You may need a different insulator to get a good seal.

My kits are not designed to be threaded as an assembly by holding the pyrex up and turning that, as I see in your video. Mine are...thread the collet body first to make sure it is tight.....then slip the pyrex cup over the collet body O-ring and seat it against the insulator.

From what I've read, kits that use a gas lens collet body and the exit orifice is a larger diameter than the mesh screen need extra CFM to compensate for the outward expanding "flare".

A few close-up pics of those gas lens kits would be good to see their detail. Also, take off the back cap, and thread in the collet body and get a shot of the torch from the back-cap side, into the torch head.

[MarkL]

Does the gas flow through the alumina cup (which I assume is using the collet body the torch came with) sound and feel comparable to the flow through the stubby gas lens? If you hold the torch up to your cheek, the gas flow should be easy to feel and hear. The discolored tungsten would indicate there is insufficient flow.

If the flow seems OK, I would guess the stubby lens is drawing air in somewhere. I've had gas lenses go bad for reasons I could never figure out, and they act just like what you're seeing. In your case it would have to be a manufacturing issue since all the lenses are doing the same thing when new.

[Poland308]

Even on the first attempt with the alumina cup it looks like you have gas flow issues. This would be a good time to use a flow meter that you hold over the end of your torch to see what your actually getting.

[Negativentropy]

More info:

Everlast 205s, 10-15 SCFM

Im confident the gas is clean, I followed Jodys advice and made the homemade air dryers and the crystals havent turned color at all.

Yeah you can see the first run with the ceramic cup (also gas lens inside) starts off with some poor gas coverage, but smooths out afterwards.

As a test I set everything up with the stubby lens, pull the torch off the hose, blocked the pyrex cup with my thumb, put soapy water on it and tried to blow air through it with my mouth - there is some very small amount of leakage at the back and where the insulator connects to the torch. I cant imagine that would be the cause.

When I blow through the detached torch the stubby lens provides about the same amount of resistance to pressure as the normal lens/cup arrangement and it feels like about the same flow coming out onto my hand and neither case produces soap bubbles.

I have tried turning up the gas to about 20scfm and it didnt make a difference. Normally when ive done everything right my tungstens stay nice and clean. Before I buy the much more expensive stuff from Jody I want to figure this out if possible. I dont do this for a living so its hard to justify some of the prices of "non import" stuff.

[Oscar]

Have you previously TIG welded without any issues with this particular tank of gas? Did this problem only start once you switched to gas lenses? How do normal collet bodies work out? Hate to think it but any leak is bad, even the one you think might be irrelevant. Not saying it's the cause definitively, but you never know.

I agree that some of the accessories are way up there in price, but in this case, it would be a wise investment to order the proper insulator for your gas lens setup. You do not have the proper insulator at the moment. A new one is ~$5.

[MarkL]

I dont do this for a living so its hard to justify some of the prices of "non import" stuff.

I hear you on the cost of some of this stuff. I'd suggest not spending the money on pyrex, it's so much more expensive than alumina cups and doesn't offer much benefit in my opinion. A quality gas lens is only a few dollars and an alumina cup is very cheap compared to pyrex. I also have never had a problem with a gas lens and an alumina cup, it's always when I use pyrex cups that I have a problem. Not sure if it's the o-ring, or the fact that it doesn't thread snug against the insulator, or what. Other disadvantages of pyrex are you can't walk the cup, and it breaks really easily.

[Negativentropy]

I went back in the shop and had another crack at it. My ceramic #8 cup with gas lens gets great coverage at 15SCFM with 15mm of stickout and at less than 10 SCFM at 10mm stick out - no problems at all. Switch to the stubby with pyrex, total disaster - even at 30 SCFM, made no difference. It feels like gas is coming out of the nozzle, it must just be totally turbulent and crap.

Im done, they are garbage, ah well at least ill get my money back. Interestingly, both those products were cheapies from China. The working ceramic cup/gas lens from ebay "RIVERWELDstore" and the shitty pyrex cup/gas lens from banggood. Who knows...

[Oscar]

I went back in the shop and had another crack at it. My ceramic #8 cup with gas lens gets great coverage at 15SCFM with 15mm of stickout and at less than 10 SCFM at 10mm stick out - no problems at all. Switch to the stubby with pyrex, total disaster - even at 30 SCFM, made no difference. It feels like gas is coming out of the nozzle, it must just be totally turbulent and crap.

Im done, they are garbage, ah well at least ill get my money back. Interestingly, both those products were cheapies from China. The working ceramic cup/gas lens from ebay "RIVERWELDstore" and the shitty pyrex cup/gas lens from banggood. Who knows...

Can you post a close-up pic of the gas lens collet body and the mesh screens? Just out of curiosity.

[Negativentropy]

Honestly I think they are just too small. That said, I did try with 1/16 tungstens and it didnt make a difference.

The frustrating thing is, they LOOK good. They are well machined and put together...

DSC_0917.JPG (27.5 KiB) Viewed 4943 times

DSC_0916.JPG (45.42 KiB) Viewed 4943 times

Here I had to grind off the deformed copper to remove the brass retaining piece.

20170530_201045.jpg (33.56 KiB) Viewed 4943 times

20170530_201215.jpg (29.03 KiB) Viewed 4943 times

[AndersK]

Have you tried with a regular #8 alumina cup on the stubby lens?
If you get better result you know the lens and everything behind up to the back cap is alright.

[ESENTI]

Hi actually there is a specific relation between gas flow per minute , diameter of alumina , seems easy but in action is not
I get get good results with alumina 6 and 7.5 liters per minute 25 cfh aprox.2.4 tungsten Where I don't get same results If I switch to
alumina 8. Alumina nozzle 8 works better on a flat level wide surface welding like a lap joint .Seems that there is a turbulence
some kind or the argon pressure behaves funny .

[ESENTI]

in previous posting was 15 cfh where is says 25 please correct it ...

[Oscar]

15 CFM sounds about right for a #6/7. I usually use around 15 CFM for my gas lenses, but then I keep a very short stickout to minimize argon use, around 1/16" 1.6mm stickout. I've gone as low as 12-13 CFM on a #8 gas lens like that.

[Negativentropy]

Have you tried with a regular #8 alumina cup on the stubby lens?
If you get better result you know the lens and everything behind up to the back cap is alright.

No the subby lens is a smaller size and wont thread onto the #8 cup.

[AndersK]

The cup for a 9/20 torch gas lens should fit.

[entity-unknown]

I notice in your video your torch angle is horrible. Fix that!

I also notice you did not swap insulators. The stock Everlast Insulator and the Stubby Gas Insulator look ALMOST identical. In fact I really can't tell the difference but there was a difference when you connect them. Using the pyrex stubby, I actually believe I recall the insulator for the Everlast being almost blatantly bigger. Still you didn't swap, so you're using the wrong insulator for one of your setups.

Prob like .1mm diff or something like that but that's huge when it comes to fluids and gas. Also I've got a Stubby Gas lens for my #8 and #20 torches from Everlast. I've used the 1/8, 3/32, and 1/16 for the #20 and 3/32 setup on the #8 and I use about 8-15 CFH depending on the job/material but I've had zero issues with gas.

I did find the stock insulator vs. the stubby insulator as said looks identical but they were not and the Everlast/stock one did not mesh quite right with the stubby lens.

A couple other common issues with gas is poor ground and/or bad electrical path to your part. I.e. if you're clipping onto a dirty welding table, and you didn't clamp your part, you can expect what will appear as bad gas coverage.

If you're alumina cup is dirty from no gas runs and just a bunch of crap that might have gotten in there, you will also experience something that's similar to having no gas. In this case your arc is just wandering around the inside and/or rim of the cup. Not as stimulating as your first rim job.

Another interesting thing I've been realizing lately is doing a bunch of practice on thin pieces of metal. You burn through and oxidize the other side and at that point you've trapped contaminates inside your piece. You will never fix this and you will continue to have really crappy results. Move to another spot or another test piece.

The last issue I've seen is a poor tungsten grind. If you have flat spots you'll have interesting Arc wander but it actually may not wander at all. Still, you will experience something like radiation burns on Aluminum if you do this. Steel wasn't as bad but that's AC vs. DC.

[ESENTI]

I have not watched the video while I post now I've seen it seem clear that there must be an air leak the tig bits cannot create
such behavior I think ...