First time using gas lens...wow!

[Rambozo]

I don't know why anyone would use a normal collet.

The gas lens cups are a lot larger in diameter than a standard 9/20, so for some tight places it won't fit, extra stickout or not.

Slightly off topic here but, with galvanized metal, you should grind off all the plating within about an inch of the weld area. The zinc in the plating boils off and if inhaled, will put you in the hospital with some pretty serious lung issues and will contaminate your body with hundreds of times more zinc that it's prepared to deal with -much akin to lead poisoning. If you've ever stick welded galvanized metal (where the heat is much more intense) that white powder that coats everything is pure zinc...

It's always a good idea to wear a respirator especially around galvanizing. For example if you are welding galvanized pipe, you may have ground it all off the outside, but it can still boil up from the inside where you might not have access to grind. And to get back on topic, it can then pop up into your weld puddle and ruin your gas lens screen.

[MoparCar]

I didn't know the gas lens would make that much of a difference. It does make sense that it would consume more Argon for the given area I guess. I hadn't really thought of that before. Sort of sounds like use them when needed, but otherwise select the best standard cup for the use?

[Rambozo]

I didn't know the gas lens would make that much of a difference. It does make sense that it would consume more Argon for the given area I guess. I hadn't really thought of that before. Sort of sounds like use them when needed, but otherwise select the best standard cup for the use?

It always comes back to the same thing; Use the right tool for the job.

[jakeru]

I agree that removing zinc near the weld, front and back side, is ideal for safety. Not always practical, or even ideal for corrosion resistance. Sometimes zinc is intentionally added to the back side or even the front side of a weld (e.g., "weld-through primer"), for corrosion resistance. Automotive body panels are a typical application, where it is commonly used this way. (Albeit I think much more often with wire feed than with TIG process, but TIG can be used here, too.) The weld-through primer does not make for a very quiet, gas lens-friendly puddle.

Steel rust is also a really good example that can be really unpredictable with flaring up and showering sparks if you encounter it with your welding arc sometimes. Sometimes it can't be removed from the back side. Let's give an example of, say, filling a hole on an automotive panel, with rust on the back side, where there is no access back there to clean it.

I do use a gas lens the vast majority of the time (> 90%), and I like them for sure. They are more expensive than regular collet bodies to replace, however, and more prone to being damaged when welding dirty stuff.