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Tony
12-29-2009, 02:55 PM
Howdy all.
Thought I'd take a minute to talk about gas lenses for tig welding.
I know quite a few members here have a tig in their shop -- and there
are probably quite a few folks here that have more experience with
them than I do, but a forum search came up with zilch -- maybe not
that many people use them or know what they do?

I don't do exotic metals welding (what, I think, the gas lenses were
born to do), but I do occasionally run into "tight" spots where its hard
to reach with a regular cup.. so I picked up some lenses.

These days its on my torch 90% of the time, with the rest just for
the real high amperage jobs (where I wish I had a water cooled torch).

A gas lens is basically screen filter that fits in the place of the collet
body.

http://img.photobucket.com/albums/0903/knucklehead/gaslens.jpg
Its intended purpose is to remove as much turbulence from the
gas flow as possible.

http://img.photobucket.com/albums/0903/knucklehead/laminarflow.jpg

This smooth flow is a big benefit to welding finicky
exotic metals.. but has two other benefits:


1. you can stick your tungsten out a lot further! (hard to reach areas)

2. you use less gas .. its more efficient. I think probably 50% less gas.

So if you're worried about the added cost of a gas lens, think about it
in terms of gas savings. Argon sure is costing me a lot these days.

Gas lenses come in alot of shapes and sizes. Most often I find myself
using a #4.

Cup sizes are measured in 1/16th's IIRC -- so a #4 is 4/16th's or about
1/4" on the ID.

Anyway, I know this is old news -- but if you've never used them
before I highly recommend you pick one up.

-Tony

Forrest Addy
12-29-2009, 03:16 PM
Yup. I like gas lense even if they are a little bulky by comparison - and they do save on shielding gas.

As a side note and I hope not a hijack, a friend of mine had a jillion little TIG welds to make so he tossed the work, jig, and tools inside his blast booth, led in a ground and stinger, covered the grating with bricks,taped off all opening, and put a coffee can with a pint of of liquid argon inside. The cold argon displaced the air from the bottom up leaving an inert atmophere to weld in. No other shielding gas needed. There was a couple of days welding to do and Zeeko (Zeko? Never could figger out how to spell it.) said later that he saved the equivalent of two 220 cu ft argon cylnders.

I didn't see the work in progress but I did see his blast booth stuck all over wth duct tape. Good idea though if you have liquid argon handy.

JoeFin
12-29-2009, 03:24 PM
I always use a gas lens 100% of the time. I was told once you get used to them, stick with them

lazlo
12-29-2009, 04:25 PM
Interesting. I got a set of gas lenses in a set of Pyrex (clear) Tig cups I bought from HTP. Haven't tried them yet, but looks like they would be great for corners.

kmccubbin
12-29-2009, 04:46 PM
Thanks Knucklehead!
I'm new to TIG, and I've been wondering what those are for, and how I would know when I should use one.

Kerry

Black_Moons
12-29-2009, 05:06 PM
Haha awsome at liquid argon trick.. Where does one even find liquid argon.
Iv heard of people making speciality ventilated rooms for stainless and other alloys where they rig up 8~ 200CF bottles and flood an entire room and do 4~8 hours welding in there. With full breathing rig of course!

Do these gas lenses apply to mig or any other processes?

Dawai
12-29-2009, 05:43 PM
HEY.. they do have a welding forum here..

Okay..

Back-purging.. I knew a guy who had a old media blast cabinet.. he put two HONDA v65 engines in there and made a V8... 320hp you could set on the table by yourself..

No transmission...

x39
12-29-2009, 05:56 PM
A very timely post as I'm preparing to order a bunch of TIG welding supplies. Thanks Knucklehead.

JoeFin
12-29-2009, 06:02 PM
I don't do exotic metals welding (what, I think, the gas lenses were
born to do), but I do occasionally run into "tight" spots where its hard
to reach with a regular cup.. so I picked up some lenses.

-Tony

The guy that introduced me to Gas Lenses wasn't doing exotic welding either. Just Chromoly and Stainless Steel pipe on a power plant job.

Althou he was the 1 who welded 8" SS pipe in a mirror in some extremely tight spaces

Dawai
12-29-2009, 06:27 PM
Joe That'd be Buck Rogers.. I went to go to lunch, the mirror was gone off my service truck.

He was welding in a two foot wide ditch with the mirror behind a group of pipes there. (Costa Mesa? 1986-7)

I've bent a 7018 rod double to weld the back side of stand pipes.. Hell, now with my vision I am more used to welding by sound anyways..

Don't laugh at Buck Roger's name, he had a cousin named "Roy".. I was drinking when I met them.. you know I was a ass.. THEM boys were tough.. full contact basketball..

macona
12-29-2009, 09:20 PM
Interesting. I got a set of gas lenses in a set of Pyrex (clear) Tig cups I bought from HTP. Haven't tried them yet, but looks like they would be great for corners.

Those are the gas-saver sets from CK Wordwide. I like them better than gas lenses.

http://www.ckworldwide.com/gas_saver.htm

macona
12-29-2009, 09:20 PM
OOps, double...

lazlo
12-29-2009, 10:18 PM
Those are the gas-saver sets from CK Wordwide. I like them better than gas lenses.

http://www.ckworldwide.com/gas_saver.htm

Yes, that's the kit I got. The glass cups are great! What's the difference between the gas diffuser/saver and a gas lens?

This is the picture on the brochure in the box, which looks an awful lot like Tony (Knucklehead)'s gas lens picture:


http://www.ckworldwide.com/images/gas_saver_web.jpg

Ken_Shea
12-29-2009, 10:45 PM
Could those help for Tig welding in a slight breeze outside as well ?

gnm109
12-30-2009, 12:14 AM
Yup. I like gas lense even if they are a little bulky by comparison - and they do save on shielding gas.

As a side note and I hope not a hijack, a friend of mine had a jillion little TIG welds to make so he tossed the work, jig, and tools inside his blast booth, led in a ground and stinger, covered the grating with bricks,taped off all opening, and put a coffee can with a pint of of liquid argon inside. The cold argon displaced the air from the bottom up leaving an inert atmophere to weld in. No other shielding gas needed. There was a couple of days welding to do and Zeeko (Zeko? Never could figger out how to spell it.) said later that he saved the equivalent of two 220 cu ft argon cylnders.

I didn't see the work in progress but I did see his blast booth stuck all over wth duct tape. Good idea though if you have liquid argon handy.


That's a very good idea. Argon is rather heavy as we all know, something like a molecular weight over 39.9 versus helium at 4+.
I wonder if it would be necessary to generate the argon from liquid. Once liberated it should stay put anyway, I should think.

I switched to gas lenses about 10 years ago and they are quite nice. I have lots of the standard nozzles in sizes from .040 to 1/8"
that I seldom use anymore since the lenses work better.
.

winchman
12-30-2009, 12:22 AM
For anything that would fit in the box, that should stop the the "sugar" that forms on the backside of chrome-moly and stainless. Anyone verify this?

How much does the argon move around as it's heated? Will it circulate enough to draw non-argon atmosphere from the top of the box down into the weld zone?

What do you do about gloves? I can't imagine using the big rubber gloves typically found in blast booths for welding, and I know they won't fit inside my welding gloves.

Roger

EVguru
12-30-2009, 04:26 AM
I always use a gas lens these days, it made welding Aluminium much easier.

The gas saver kits are just gas lenses combined with Pyrex cups. I thought about buying one, but they're not stocked in the UK and you can't rest on or walk the cup. I do that a lot at the moment because I haven't got room for a welding bench and I've been doing all my TIG work stading on one foot with the other on the pedal.

Purge chambers or glove boxes are quite common and you need to get all the air out for good welds. I've seen this flexible chamber from CK.

http://www.ckworldwide.com/images/purge_2.jpg

http://www.ckworldwide.com/purge_chamber.htm

Tony
12-30-2009, 09:57 AM
Tig (& gas Mig) + outside + breeze = usually a bad combination. I've done
it once or twice but you must be sure to set up a lot of baffling. Tin foil
usually works in a pinch. For both tig/mig you'd want to up the gas flow.
You'll know almost immediately if your gas is blowing away faster than the
weld is cooling.

I'm guessing but I'd say "gas saver" is just a CK proprietary version of the
standard gas lens.

I've always liked the pyrex cups but have never used one. Apparently,
the gain in visibility, especially for small work, is unparalleled.

Remember that, if you go to a gas lens, you'll need an additional insulator
between the cup and the torch's insulator. Its basically a step-up ring,
but your torch will suck air in without it. You could also get a nasty
shock if you have an HF-start.

I've always been attracted to the "pencil" style straight torches. Anyone
ever use one? I'll have to pick one up.

A foot control, IMHO, is almost mandatory for TIG welding. I've made do
for years without one, and its doable -- my current TIG welder's accessories
have ludicrous pricing -- $500 for the foot control.. I've made due with a
potentiometer hot glued to a heavy steel block -- I just move it around with
me, somewhere close. I've been wanting to retrofit a guitar pedal -- but
its one of those projects that you only think about the moment you really
need to weld something.

-Tony

Tony
12-30-2009, 10:04 AM
Paul, that purge chamber looks great.
Notice they have a wire feeder mounted on the torch -- probably
easier than trying to hold a 18" long piece of filler in there.

BigMike782
12-31-2009, 08:18 PM
If your gas supplier pumps on site the may have dewar flasks they rent and you could buy some liquid argon.

I find gas lenses a bit awkward and I did not see much difference between lenses and regular cups but then don't do as much TIG as some of you might.