[a_j_p]

I hobby weld, have done so for years. Primarily I make bicycle frames, all chromoly. I have an Everlast welder that I use with a water cooled torch and have used this setup for the last 4-5 years without issues.

Recently, in the middle of a bike frame I had a flex head torch fail (copper hose for a water line cracked). I cleaned and replaced the head like I have done in the past. But now however I cannot weld no matter what I try/do.

As soon as I fire up the welder I get instant sparking, the tungsten turns black and balls up... It is driving me crazy. I have checked for gas leaks, I have tried several different torches that I have (additional water cooled torches I don't like as much, air cooled torches) and I get the same result with everything.

The metal is clean, the argon bottle nearly full and flowing. Changing the gas flow rate doesn't make a difference, neither does swapping for new consumables... Everything I do just instant crap from the time I hit the pedal.

Any other suggestions? The only thing left for me to try is having the gas tank swapped/checked, but these symptoms don't seem consistent with moisture in the tank - plus everything was working awesome prior to the torch head failure (tank is ~3/4 full).

Before and after photos posted below if it helps...

The settings used for both images, for reference:
- Pulse Tig: 100 Amps, 2PPS, 25% On Time, 20% Background Current
- #8 Ceramic Cup, Gas Lens, ~3/8" Stickout, 1/16" tungsten (2% lanthanated)
- ~18CFH, 100% Argon
- Steel cleaned near weld inside and out with scotch-brite first, then wiped with acetone

Also for reference, I get the same results whether pulse tig welding, straight current DC welding, or even on some cleaned A36 mild steel tubing I have lying around from another project.

Also for reference, I can get a clean weld to start if the stickout is <= 1/32" - but anything greater than that (even 1/16") and I get problems... Welding bike frames with 1/32" stickout is not possible, there are parts of the frame where I need the stickout to be up to ~1", and in the past could weld without issues if I was mindful of the gas flow and work-holding.

[Oscar]

You are not getting argon flow, or the flow is picking up air, plain and simple. Disassemble your torch to make sure you didn't put the collet in reverse and/or is crushed.

I had a similar issue about 4-6weeks ago. I tried EVERYTHING. Even routing the argon straight to the torch bypassing the machine. The last thing I tried was the culprit: a cheap wp-9/20 gas lens collet body from Welding City. I tried other ones that were new, even had the little red cap on the threads to protect them. They were old, but other than that brand new. With every single one of them, I got the same results you are seeing. Somehow the argon was not flowing past the collet body or was picking up air somehow. I switched to a standard 9/20 collet body/collet/cup and VOILA! I even used the same collet that I was using with the junk gas lens collet body. Welded perfectly. Try it. You never know.

[a_j_p]

Thanks for the reply...

Man I've windexed the argon lines and connections from tank to handle, I've swapped for fresh consumables, even swapped torch assemblies, one of which is brand new... If I'm picking up air I cannot for the life of me find where, unless it's inside the machine assembly. Otherwise gas is flowing, and pressure builds if I cover the head without a tungsten... I've double checked assembly of everything and connections many times now. It's making me crazy - should be simple I agree.

[a_j_p]

I will try with the standard collets though and let ya know... Hopefully that's it. I have the same cheap gas lens kit probably... Not sure why trouble with them now and not before, but at this point I'll try anything.

[Oscar]

I will try with the standard collets though and let ya know... Hopefully that's it. I have the same cheap gas lens kit probably... Not sure why trouble with them now and not before, but at this point I'll try anything.

It was definitely odd for me as well. It had worked fine before, it's like it just didn't want to work anymore. Very odd indeed. After that, I threw out all those 9/20 cheap gas lens collet bodies. Don't forget to check that the gas port inside the torch is not being blocked off by the collet body. Thread-in the collet body completely without the backcap installed, and look inside the torch from the backcap end. You should be able to see the gas port right behind the inner end of the collet body. If it is not visible, then it's being blocked, or if you can only see a little bit, it's partially blocked. While you're there, look at the backcap to make sure the o-ring is still there.

[a_j_p]

Oscar man I owe you one... swapped back for the standard collet assembly that came with the torch and everything works great. This drove me nuts, I was worried somehow coolant got into the gas line so I kept purging it... the whole time I was swapping torches and consumables though I always was using those gas lenses without thinking about them at all.

Why things would work up until the torch head started leaking and then not again is beyond me, but like you, I'll be throwing out all of those cheap gas lens parts.

While we're on the topic? Any gas lens for a #20 torch you (or anyone else) recommend/endorse? I am assuming the ones on Weldmonger are decent/good?

[LtBadd]

While we're on the topic? Any gas lens for a #20 torch you (or anyone else) recommend/endorse? I am assuming the ones on Weldmonger are decent/good?

Can't go wrong with CK brand

If you got to their literature page and look at the technical guide (form 116) also the parts poster and you'll see part numbers of their various tig consumables

[Poland308]

I’ll second the CK chant. I’ve never been unhappy with anything CK that I’ve bought.

[tweake]

I’ll second the CK chant. I’ve never been unhappy with anything CK that I’ve bought.

+1
fan of their gas lenses and gas saver kits.

[Spartan]

I’ll second the CK chant. I’ve never been unhappy with anything CK that I’ve bought.

+1
fan of their gas lenses and gas saver kits.

+1
CK is all I buy these days. And some Furick cups...

Had a big box of CK consumables I just received that I went to take a pic of for this post, but alas, I already dropped it off at the shop. Getting a big box of CK parts in the mail is like Christmas.

[Oscar]

Oscar man I owe you one... swapped back for the standard collet assembly that came with the torch and everything works great. This drove me nuts, I was worried somehow coolant got into the gas line so I kept purging it... the whole time I was swapping torches and consumables though I always was using those gas lenses without thinking about them at all.

Why things would work up until the torch head started leaking and then not again is beyond me, but like you, I'll be throwing out all of those cheap gas lens parts.

While we're on the topic? Any gas lens for a #20 torch you (or anyone else) recommend/endorse? I am assuming the ones on Weldmonger are decent/good?

It's weird huh! I duked it out with my setup for at least 3 hours, swapping everything except those cheap gas lens collet bodies. It's always the last thing you check.

If you're gonna use gas lens collet bodies, CK or WeldTec are the only way to go. WeldTec stuff is not very common, but they make killer stuff. You can get it from Weldfabulous as I have in the past.

Or you can go 100% fool proof. Make your own gas lenses from standard parts like me. Works awesome AND cheap!



Only time this won't "work" is if you need a cup larger than a #12. I don't think there are any standard cups larger than 12.

[tweake]

i think its was miller gas lens that are also meant to perform very well and are of good quality.
but i still like CK.
just which i had better access to their gear. they don't like to sell direct overseas and the local agents hold little stock and tend to screw us over on price.

comon jody i want to by a new tig torch off you!

[a_j_p]

I ordered some ck stuff to try out, thanks for all the input. I'll let you guys know how things work when it arrives.

Also, interesting on making your own gas lenses... I always assumed the radial hole pattern in the collet body played a part along with the mesh, but if it works well than I'm probably assuming wrong. I don't generally use anything larger than an 8 cup so it may be worth trying if I run into more issues later.

[Oscar]

They sell SS mesh screens in common TIG cup sizes on eBay. The spacer rings are just 035 SS TIG rod curled up. Just punch a hole for the tungsten and instant gas lens. I used a shortened collet as a guide but its not even necessary. The radially drilled holes still do their job to spread the gas out, and then the mesh screens create the more laminar flow for when you need to use a long stick out.