# CO2/Argon  5%, 10%, 15% ??  When? Why?



## graham-xrf (Jan 12, 2021)

After a little tangle not getting through the Brexit border, the new welder has finally arrived. I have found a place not too far away that will always return the entire deposit on a gas bottle, no matter how long you keep it (years), so it's never on hire. They supply the three different mixes of CO2/Argon, and also Argon Pure, and Oxygen, and Acetylene.

My welder does MIG, and Lift-TIG (and some other options for stick, polarity, AC or DC). To choose a particular gas mix, one needs reasons.
So - what are the conditions that would motivate one to choose (say) 5% CO2, or 10% maybe. What drives the choice?


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## DavidR8 (Jan 12, 2021)

I'm far from an expert but TIG requires 100% Argon, MIG is 75% Argon + 25% Co2


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## benmychree (Jan 12, 2021)

For MIG, I use straight CO2, that is the cheapest and the best penetration, but an argon mix will give smoother welds.


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## DavidR8 (Jan 12, 2021)

Yes, I totally forgot about straight Co2!


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## Buffalo21 (Jan 12, 2021)

I use 90/10 on my Miller 350P pulse mig and 75/25 on my Miller Millermatic 252


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## General Zod (Jan 12, 2021)

benmychree said:


> For MIG, I use straight CO2, that is the cheapest and the best penetration, but an argon mix will give smoother welds.


Straight CO2 does make for a hot, fluid puddle, but you should check out the video Jody did on welding a Jeep bumper where he also tested some welded samples by putting them in a 20Ton press, one was welded with straight CO2 and the other with 75/25 Argon/CO2.   The winner, as determined by Jody, would surprise you, as it did me.


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## Janderso (Jan 12, 2021)

Benmychree is correct in my experience.
This may help


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## Janderso (Jan 12, 2021)

General Zod said:


> Straight CO2 does make for a hot, fluid puddle, but you should check out the video Jody did on welding a Jeep bumper where he also tested some welded samples by putting them in a 20Ton press, one was welded with straight CO2 and the other with 75/25 Argon/CO2.   The winner, as determined by Jody, would surprise you, as it did me.


I need to check this one out.


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## Janderso (Jan 12, 2021)

DavidR8 said:


> I'm far from an expert but TIG requires 100% Argon, MIG is 75% Argon + 25% Co2


Whoa,
I didn't recognize you. Hi David. I like it = chips.


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## General Zod (Jan 12, 2021)

graham-xrf said:


> After a little tangle not getting through the Brexit border, the new welder has finally arrived. I have found a place not too far away that will always return the entire deposit on a gas bottle, no matter how long you keep it (years), so it's never on hire. They supply the three different mixes of CO2/Argon, and also Argon Pure, and Oxygen, and Acetylene.
> 
> My welder does MIG, and Lift-TIG (and some other options for stick, polarity, AC or DC). To choose a particular gas mix, one needs reasons.
> So - what are the conditions that would motivate one to choose (say) 5% CO2, or 10% maybe. What drives the choice?


 
For welding Mild steel using the short-circuit transfer process, the addition of argon to CO2 provides "smoother" welds, and may also provide higher tensile strength and enhanced ductility via better Charpy V-notch ratings.  25% CO2 concentration is good all-around blend since the Argon component costs more than the CO2 component, but you'll rarely see less than 75% in the mix because you start to lose the advantages of argon but still have to pay for the premium of having argon in there anyways.

Using C10 can provide higher Yield and Tensile strengths and better Charpy V-notch performance, as seen from this snippet from Lincoln:








Less than 10% CO2 is usually reserved for spray-transfer or pulsed-spray transfer modes.


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## G-ManBart (Jan 13, 2021)

To add just a bit to what General Zod said, 75/25 (argon/Co2) is very common for short-circuit MIG, but if you want to get into spray transfer MIG, you need a higher percentage of argon.  Here in the States that usually means 90/10, 95/5 or 98/2.  Not all welders have enough power to get into spray transfer mode, so it may not even be an option for you.

Using a MIG welder with a spool gun or push/pull gun for aluminum requires 100% argon.

Using a MIG welder for stainless steel requires one of several blends....helium/argon/Co2, argon/O2 or argon/Co2.

TIG requires 100% argon, or an argon/helium blend.


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## graham-xrf (Jan 13, 2021)

G-ManBart said:


> To add just a bit to what General Zod said, 75/25 (argon/Co2) is very common for short-circuit MIG, but if you want to get into spray transfer MIG, you need a higher percentage of argon.  Here in the States that usually means 90/10, 95/5 or 98/2.  Not all welders have enough power to get into spray transfer mode, so it may not even be an option for you.
> 
> Using a MIG welder with a spool gun or push/pull gun for aluminum requires 100% argon.
> 
> ...


You guys are just great! A beginner could go for quite a long time without discovering stuff like this. Thank you all!


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## cbrasher (Jan 13, 2021)

graham-xrf said:


> You guys are just great! A beginner could go for quite a long time without discovering stuff like this. Thank you all!


Graham,
 I am new here but one thing I would caution you on: check your regulator. My new Hobart welder came with a regulator labeled for Ar/CO2 ONLY. I thankfully had a straight CO2 regulator from the other welder, but I was surprised that it wasn't capable of doing both for whatever reason. If you have an old one, then you are like me: ALL SET! 
  I am glad to see this info as I ran out of CO2 last night. I have a brand new bottle in the barn but was going to swap the empty and now have a decision to make as to what to get for my new spare.

Corey


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## G-ManBart (Jan 13, 2021)

cbrasher said:


> Graham,
> I am new here but one thing I would caution you on: check your regulator. My new Hobart welder came with a regulator labeled for Ar/CO2 ONLY. I thankfully had a straight CO2 regulator from the other welder, but I was surprised that it wasn't capable of doing both for whatever reason. If you have an old one, then you are like me: ALL SET!
> I am glad to see this info as I ran out of CO2 last night. I have a brand new bottle in the barn but was going to swap the empty and now have a decision to make as to what to get for my new spare.
> 
> Corey


More often than not, the flow meters that don't show Co2 are marked that way because they have less mass, and are more prone to freezing with 100% Co2.  There isn't much difference in flow rate between Co2 and 75/25 when you look at dual scales, so that's not really a problem...you'd be off by a bit from what the gauge reads, but still close enough it shouldn't matter.

Co2 runs a bit hotter, but leaves more spatter compared to 75/25.  For smaller machines or someone trying to really save money Co2 can be a good choice.  My LWS is cheap...a 330 bottle swap of 75/25 only costs me like $65, and my machine has more power than I can imagine ever needing, so I stick to that rather than clean up spatter.


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## kb58 (Jan 13, 2021)

I always assumed that CO2 is used (in any amount) purely for cost reasons.


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## Weldingrod1 (Jan 13, 2021)

Yes, pure CO2 is only for cost reasons. All the others weld better. But, getting a paintball tank refilled.is pretty easy...

Sent from my SM-G892A using Tapatalk


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## cbrasher (Jan 13, 2021)

Well, I continue to learn. Praxair says the reasons the costs are low is because CO2 is 800psi while the Ar/CO2 25% tank has to pass static pressure test @3700 PSI and is filled at 2200 PSI. So product exchange for CO2 to ArCO2 is $150 because the bottle cost is so much higher while the CO2 is $28 exchanged. Something new for me!


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## Boswell (Jan 13, 2021)

so does that mean that you get approx 3 x as many cubic ft of Ar/CO2 (2200psi) as you would pure CO2 (800psi)  that would seem to mitigate the price difference somewhat


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## jwmelvin (Jan 13, 2021)

I believe CO2 is a liquid in the cylinder so you get plenty of volume without the increased pressure.

That’s why pure co2 is sold by weight not volume


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## General Zod (Jan 13, 2021)

kb58 said:


> I always assumed that CO2 is used (in any amount) purely for cost reasons.


I would not say that is completely accurate.  Try short circuit MIG welding with 100% argon, and then with C25.  Then cut-polish-etch the samples to see the differences.


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## graham-xrf (Jan 13, 2021)

OK - now we get onto territory I have more knowledge on.

Thanks to @cbrasher for mentioning the regulator. The calibration of regulators does depend on the gas density. So yes - you do get regulators that are calibrated for Helium, Argon, Oxygen .. whatever. This is OK so long as always, the proper gas is in it's own color coded cylinder.

Of course, it's a darned pain if you have gas mixes. You can have a lookup scaling factor to let you use a regulator for one gas, adjusted for another, or a mix. Here is where one can get out the old high school notes about partial pressures.

I forgot some gases are sold by weight. Of course they are, especially those that are liquid under pressure, like butane.
It gets complicated with stuff like acetylene, which is shipped dissolved in acetone.

I did not know CO2 has a liquid phase. I know that I needed compressed air filtered completely free of CO2 to stop it turning solid and blocking dewars when used for cooling IR cameras, and I watch frozen CO2 turning from solid straight into gas without going through being a liquid (dry ice). Maybe CO2 can be liquid at high enough pressure - I don't know.

The volume of gas you have is escaping into standard atmospheric pressure - is that about 14.5 pounds/sq inch.
The way to figure how much gas you have to use is then the volume of the cylinder x the pressure in it when "full", divided by standard atmospheric pressure.
Volume available = (Volume of cylinder x pressure)/(standard atmospheric pressure).

Definitely there is more to using CO2 than just the (attractive) lower cost. As @General Zod has mentioned, the character of the arc, the behavior of the weld pool, and the penetration of the weld are changed. Of course, I am just setting out on welding stuff. Clearly I cannot simply buy and try set of gas bottles in all combinations of weld mixes. I had to get the real solid information.


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## kb58 (Jan 13, 2021)

I hear welding with hydrogen goes pretty fast...


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## G-ManBart (Jan 13, 2021)

graham-xrf said:


> Thanks to @cbrasher for mentioning the regulator. The calibration of regulators does depend on the gas density. So yes - you do get regulators that are calibrated for Helium, Argon, Oxygen .. whatever. This is OK so long as always, the proper gas is in it's own color coded cylinder.



Just so we don't confuse the folks in the States who read this....there is no color code system in place for gas in the U.S.


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## Shootymacshootface (Jan 13, 2021)

I recently switched from straight C02 to 75/25 CO2 argon mix. Now my welder is the machine that it was meant to be. I wish that I didn't wait so long to do it.

The lure of dirt cheap CO2 and no strings attached on the bottle was just too irresistible. I have a friend that works for the 2nd largest soft drink company in the world and a full bottle costed me $15.


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## Lo-Fi (Jan 14, 2021)

The short and curlies are:

Use straight argon for TIG, "argo-shield 5" (5% CO2) for MIG. Those two cover _everything_ your welder is capable of.

I started out MIGing with straight CO2. Once I discovered the joys of the argon mixes and hobby suppliers popped up (I had a deal with the village pub for CO2 bottles), I swore I'd never go back. Smoother, more control, less messy, instantly better welds. You need that 5% of the slightly reactive CO2 with the argon, which is why a straight argon cylinder won't do both processes.

You _can_ MIG with straight CO2 or straight argon, but there's _no gain_ to be had at hobbyist level and you won't get the best results. The mixes have been developed and are used the world over for good reason. For how much gas you're likely to use, there's not even much of a financial incentive.


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## Janderso (Jan 15, 2021)

You guys ever, "stir" your tanks?
I saw a video Jodie did where he lays the CO2-Argon tank on it's side and rolls the tank to mix the 2 gasses.
Like most of you, my tanks sit on the cart for months on end. I have never stirred my tanks.
Just curious.


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## Lo-Fi (Jan 15, 2021)

No, I'd not heard of that, but I can see why you'd do it now you mention it. I've not welded in ages, I'll do a run, "stir" and do another run and report back next time I do. Will be interesting.


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## General Zod (Jan 15, 2021)

Gases do not settle in the long-term.  At first they can, such as if Argon is introduced into a small confined space in our atmosphere, but due to entropy and the mean-particle velocity (which can be calculated), they will be homogeneously blended.   For if they did settle, our atmosphere would have different layers of Oxygen/nitrogen/Argon/etc/etc.  Someone would have to "stir the Earth" to make it into "air" constantly.


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## foleda (Jan 15, 2021)

General Zod said:


> Gases do not settle in the long-term.


This was my initial reaction but then it occurred to me that, at high pressure CO2 Ar mixtures might have a liquid phase
that would indeed settle.  A quick google turned up actual data.  At room temperature 25% CO2 in argon does not form
a liquid phase at any pressure so no need to stir your tanks.  However, if you are welding in the arctic (-40C) a liquid will
form above 2000psi or so.


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## G-ManBart (Jan 15, 2021)

All of my mix gas bottles have a valve with "DT" on the stem.  Some call that a dip tube, some a siphon and others an inductor tube.  As I've read, it draws from two different parts of the tank (Co2 near the bottom) to help draw them out in the correct proportion.  Look at a 100% argon bottle and it won't have that "DT" stamped on the stem.


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## rwm (Jan 15, 2021)

Janderso said:


> You guys ever, "stir" your tanks?


They tried that on Apollo 13... I would avoid it.
Robert


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## pontiac428 (Jan 15, 2021)

Stratification, as I've heard anecdotally, can occur at critical points, but Fick's Law says it won't be an issue. Does the syrup settle out of your Coca Cola? No? Same idea.


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## General Zod (Jan 15, 2021)

G-ManBart said:


> All of my mix gas bottles have a valve with "DT" on the stem.  Some call that a dip tube, some a siphon and others an inductor tube.  As I've read, it draws from two different parts of the tank (Co2 near the bottom) to help draw them out in the correct proportion.  Look at a 100% argon bottle and it won't have that "DT" stamped on the stem.


I would love to read that.   Nothing that I've read leads me to believe gases will stay separated like that.


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## G-ManBart (Jan 15, 2021)

General Zod said:


> I would love to read that.   Nothing that I've read leads me to believe gases will stay separated like that.


Going off a number of threads, the dip tube/siphon/etc might be more for mixing as the tank is filled, rather than for mixing output.  Found this:





__





						Gas cylinders venturi dip tube - The BOC Group plc
					

A gas cylinder has mounted therein a venturi device through which the constituents of a gas mixture pass when the cylinder is being filled with gas. The venturi device causes rapid and thorough mixing




					www.freepatentsonline.com


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## General Zod (Jan 15, 2021)

Yes Matheson TriGas says the same thing - that it has to do with the initial.  An improperly mixed mixture is more likely to stay somewhat stratified than one that is properly mixed.

Matheson Article.


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## graham-xrf (Jan 15, 2021)

@General Zod has it exactly right. They mix! Also, the speed of the mixing is really fast - bullet-like!

You can wonder about how we have in the atmosphere the (rare on Earth) gas Helium around, being as it comes from radioactive decay of Thorium, Uranium and Radon, and is in some concentration in natural gas wells in North America.  It is a very light element, and supposedly "floats off into space". Does it?  Yeah - much more complicated! I won't get into all the mechanisms about mean free path, and collision probability, and achieving escape velocity. 

I tried it while diagnosing a leak in a vacuum furnace using a mass spectrometer Helium leak test instrument. I walked around with the leak tester and ended up about 40 metres away at the end of the car park outside, and it was still squealing. We tried again later (after leak fix). There seemed hardly any time lag between the little puff of Helium, and detecting it right across the industrial property. The Helium was everywhere, not quite instantaneously, but damn fast! It takes about 20 minutes to dissipate. It only "floats up" readily if confined in a party balloon. Otherwise, it mixes, no need to shake nor stir.

[Edit: Re: @rwm  Robert's  Apollo 13 reference to "stirring the gas tank" begs the question - why did NASA bother? I get it they were stirring what was a liquid at the time  (Oxygen). ]


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## General Zod (Jan 15, 2021)

by the way graham-xrf, what you need is a Frankenmixer.  You can mix any percentages you want.  And it works, plain and simple.


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## G-ManBart (Jan 15, 2021)

graham-xrf said:


> [Edit: Re: [USER=23938]@rwm  Robert's  Apollo 13 reference to "stirring the gas tank" begs the question - why did NASA bother? I get it they were stirring what was a liquid at the time  (Oxygen). ]



Yes, it was a liquid oxygen tank.  They were doing a stir to keep the slush from stratifying.


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## graham-xrf (Jan 17, 2021)

General Zod said:


> By the way graham-xrf, what you need is a Frankenmixer.  You can mix any percentages you want.  And it works, plain and simple.


Ohooo - I do like that! Essentially flow meters in the separate gas lines from bottles of Kosher pure.

I ventured out yesterday (carefully, sans vaccine), and picked up a *20 Litre *volume bottle at* 200bar *of* 5% CO2/Argon* mix.
Converting to US units that's 2900.75psi and the volume is 0.7063 cubic feet.
So at standard pressure 14.503psi, that s close to 141.2 cubic feet. That's enough to do a whole lot of MIG beginner mess-ups!

They had "run out" of pure Argon, and had bottles on order. That's OK. I will play MIG for the time being, but on the way back, I was thinking about a gas mix method. This gadget just bypasses the "stratifying" phenomenon. One thing I did get from this discussion is that you don't get to successfully mix the gases like shaking a Martini ! I guess laying the bottle on it's side for a while now and then might help a bit.

Gas mixing to include 2% Oxygen, and choosing the varied percentage of CO2 is probably a fine nuance optimization for the very advanced welder to add to current control, voltage, electrode diameter, metals involved, etc.

*Thin stainless?*
I had thought about playing with some *TIG* is to make up a bigger stainless steel tray by cutting an end off two trays, and welding them together. This would be working with thin stainless, a bit like car body welding. I guess 0.8mm stainless *MIG* might well do it OK also.

*Checking on the value of MIG wire deals.*
Duh .. some will sell weld rods and reels by weight. Some by length. Some in inches, feet, yards, metres, cm, whatever.
Some by number of rods in a bunch.  This can actually be quite good if the rod happens to be coated with slag cover or gas generation chemicals. It gets more complicated if the stuff is cored. One gets tired of multiplying or dividing by metal density and wire diameters after units conversion. I will find the app/spreadsheet soon.

*TIG kit. Selection and costs.*
Here I mean the handle, tungstens, pink cups, fittings etc. Everything other than the welder itself. This is a whole other research that we trawl eventually.


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## G-ManBart (Jan 23, 2021)

graham-xrf said:


> *TIG kit. Selection and costs.*
> Here I mean the handle, tungstens, pink cups, fittings etc. Everything other than the welder itself. This is a whole other research that we trawl eventually.



I can make the tungsten selection simple for you....get 2% Lanthanated and use it on everything.  There are some special cases where another type will work better, but it's nothing you're going to run into for a long, long time.  3/32 will cover most of of what the typical person needs, but having 1/16 and 1/8 on hand will be nice options to have for certain applications.  

For cups, #5 to #8 in standard pink alumina cups will get you started.  I like #5 for smaller aluminum work, and a #8 gas lens for almost everything else, but there's a lot of wiggle room in between.  For stainless you want a bigger cup compared to steel or aluminum.  Gas lenses are a nice option, but don't get tricked into thinking they're for saving gas....they're simply for getting better gas coverage for a set amount of flow.  You wind up saving a bit of gas, but that's a side benefit.


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## rwm (Jan 23, 2021)

Honestly, I have Ceriated, Lathanated, and Purple tungsten and I can't really tell the difference on anything! The new Purple tungsten is supposed to be multipurpose. I'm sure a professional could tell the difference, but for the hobbyist I would take G-Mans advice. I almost always run a 1/16" electrode but I rarely weld north of 150A. I have yet to melt a tungsten. Gas cups are also not critical and somewhat dependent on the geometry you are welding.
Robert


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## 7milesup (Jan 23, 2021)

I almost always use 3/32 tungsten.  I also  have switched to CK wedge collets.  One of the best things I have done.  The split collets are terrible.


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## 7milesup (Jan 23, 2021)

cbrasher said:


> Graham,
> I am new here but one thing I would caution you on: check your regulator. My new Hobart welder came with a regulator labeled for *Ar/CO2 ONLY.*
> 
> Corey


I read that different than you.  To me, it means it is to be used with Argon or CO2 only, not helium or whatever else.  I don't read that as being for an Ar and CO2 mix only.  That would make no sense.


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## G-ManBart (Jan 23, 2021)

rwm said:


> Honestly, I have Ceriated, Lathanated, and Purple tungsten and I can't really tell the difference on anything! The new Purple tungsten is supposed to be multipurpose. I'm sure a professional could tell the difference, but for the hobbyist I would take G-Mans advice. I almost always run a 1/16" electrode but I rarely weld north of 150A. I have yet to melt a tungsten. Gas cups are also not critical and somewhat dependent on the geometry you are welding.
> Robert



I've used the new tri-blend tungstens (some are purple and some lime green) enough that I don't think anybody can see a difference on them for steel or stainless.  On aluminum they seem to very slightly hold a point better than 2% lanthanated, but it's a really minor difference and certainly not worth the price difference.  

I've also tried a lot of different brands and found that Midwest Tungsten Service (sells on both eBay and Amazon) are probably the best bang for the buck going.  Nobody makes tungstens in the U.S. now, so they all come from China with a handful being made in Germany and Austria (at much higher prices).  I've used quite a few packs from MTS so far and the quality seems consistent, and they have tons of feedback on eBay and Amazon that echoes what I've experienced.


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## rwm (Jan 23, 2021)

7miles-I will have to try those collets. I have had issues with the splits.
I think Graham is interpreting the label correctly. I doubt you could use the same regulator for pure Ar and pure CO2. Their viscosities differ considerably. It is labeled for a MIG blend.
Robert

EDIT:
Maybe I misunderstand? I was thinking about the Flow meter side.
R


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## 7milesup (Jan 23, 2021)

RWM ---> Here is a linky to the collets. I will never use a split collet again.<---


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## graham-xrf (Jan 23, 2021)

7milesup said:


> RWM ---> Here is a linky to the collets. I will never use a split collet again.<---


Thanks for the tip. I will be looking for non-split collets. The link place pops up a warning they only ship to UK on orders over $135, and come to that, the import requirements since 1st January may be new.

My welder (from Poland) at first got returned to the supplier, who promptly messaged me that they were going to try again, with new paperwork. It has arrived now, and from my first lookings, it is a super machine. Very "German" looking.

The instructions say that the TIG torch must be a TIG 17V type with s gas valve at the handle. Being a TIG newbie, I am guessing that that is a hand version of flow control that is also done by foot pedal control in some systems. I really have no idea.

The gas bottle I have right now happens to be 5%CO2 with 95% Argon, intended for MIG.  To begin, I have quite a lot to play with in welding up the 40mm (about 1.5") steel angle sections, and I expect I will be OK with the supplied 0.8mm (0.03") wire.

My eye is on TIG for welding the type 201 stainless steel tray for my lathe. It's to be made of two 60cm x 40cm food industry trays joined together. They look about 1.6mm thick. Like doing car bodies, I suppose it _could_ be done with MIG as a series of short little dabs, and then grind back the inevitable splodges, but here is where I thought to use TIG, with a 308 stainless filler, which is supposedly good for joining austenitic stainless of the same type. There is the choice also of 316 filler with a tad more silicon, supposedly good for welding 201 also. You can bet I will be trying it out on the off-cuts first!

So, for all this, I have to put together the gas tube and connection to the welder, the handle (air cooled?), and the most likely useful collection of little parts (as per your link). I suppose I will have to invest in a second bottle deposit for the pure Argon, which then makes possible a Frankenmixer as suggested by @General Zod earlier. That would be for the future.

I see in your link https://weldfabulous.com/welding-supplies/tig-welding/tig-consumables/ there are various  "Gas Saver Kits" like this one with a Pyrex Cup.


That one listed at *$38.99*
I take it the mesh thing at lower left is one of those "gas lenses" that apparently make a smooth gas flow straight down.

Then there is the little tube with the sloped exit.



We have two things competing for the name "Gas Lens". Both are 3/32"




Prices are *$11.69* for the left side  .. ..                             and *$22.42* for the one on the right

The variety of designs (and prices) from every vendor and his dog seem infinite. A whole cluster of tiny bits and pieces, and I haven't yet got to the sharp pointy tungsten bits, available in all angles and diameters, and some folks grind them to their own preference.

Sure - I am happy to go with the starter recommended default. Right now, it's still a little hard to see which that is!


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## Liljoebrshooter (Jan 23, 2021)

I agree on the split collet from CK.  I use them at work everyday.   We usually run pretty hot on one of our stations,  usually at 175 amps.    You will fry a split collet in a jiffy.  They will be twisted up in a day.   The wedge collet will last for weeks. 

Joe


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## graham-xrf (Jan 23, 2021)

rwm said:


> 7miles-I will have to try those collets. I have had issues with the splits.
> I think Graham is interpreting the label correctly. I doubt you could use the same regulator for pure Ar and pure CO2. Their viscosities differ considerably. It is labeled for a MIG blend.
> Robert
> 
> ...


When I used Argon before, in a vacuum furnace, was where I first came across the need to have the gas regulator be correct for the gas density. The regulators are much the same, near identical looking, but the difference is in the calibration. I recall that they even had a "conversion graph" to allow to use the "wrong" regulator, and get to the "adjusted" reading for the different gas.

I don't know what is involved in adjusting the calibration, but I got the impression it had to be reasonably easy, because the supplier seemed able to do it on fast turnaround.


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## rwm (Jan 23, 2021)

They are overcharging for shipping. $10 for an envelope with 5 tiny collets?
What is the difference between the "gas saver" and the regular?
Robert


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## General Zod (Jan 23, 2021)

graham-xrf said:


> Thanks for the tip. I will be looking for non-split collets. The link place pops up a warning they only ship to UK on orders over $135, and come to that, the import requirements since 1st January may be new.
> 
> My welder (from Poland) at first got returned to the supplier, who promptly messaged me that they were going to try again, with new paperwork. It has arrived now, and from my first lookings, it is a super machine. Very "German" looking.
> 
> ...


No they are not competing for the same name. The one on the left is for 9/20 style torches ( the copper threaded portion is actually smaller than the picture suggests, and definitely smaller than the one on the right), and the one on the right is for a 17 style torch.  The one on the right is also known as a "stubby" gas lens collet body because it's specific purpose, aside from creating laminar flowing gas, is to allow the user to use 9/20 style cups, which are shorter in OAL than the ones for 17/18/26 style torches.  I have all of this in my collection.  Literally everything posted here thus far, I have it.  I even have quad-blend tungstens that no one has mentioned


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## rwm (Jan 23, 2021)

Zod- How do you feel about the wedge style collets? and which one do I want for my 17 torch?
Robert


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## G-ManBart (Jan 23, 2021)

Liljoebrshooter said:


> I agree on the split collet from CK.  I use them at work everyday.   We usually run pretty hot on one of our stations,  usually at 175 amps.    You will fry a split collet in a jiffy.  They will be twisted up in a day.   The wedge collet will last for weeks.
> 
> Joe



Air-cooled, or water-cooled torch setup?  I have a pile of split collets, so I haven't bought any of the wedge style.  I'm running a Syncrowave 250DX TIGRunner water-cooled setup and can run 200-250A for as long as I want and not have issues with the split collets.  I can't even remember the last time I had to change one, but it was likely because I was too aggressive tightening the tail cap.  I can't imagine ruining one in a day.


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## General Zod (Jan 23, 2021)

rwm said:


> Zod- How do you feel about the wedge style collets? and which one do I want for my 17 torch?
> Robert


I don't know which ones you want, because you should decide for yourself.  Wedge Collets from CK (I have to be specific because they invented them AFAIK, and there are off-brands now as well) work, and they last long, plain and simple.   At the same time, I have more regular copper collets than CK wedge collets.  Once when I was a rookie, back in '10 or '11, I did manage to twist a regular collet because I switched out a fouled tungsten and then over-tightened the back cap immediately while the whole torch (and collet) was still hot.  The softened copper collet twisted, and had to be replaced.  Once I learned on my own that could even happen, I've been very careful ever since and have never caused that to occur again.  I say "caused" because it's all operator error.  The back cap doesn't need to be torqued down that hard to begin with.  Snug + a nudge more and that's it.

The only disadvantage to wedge collets is that the slanted wedge changes the angle of the tungsten.  The longer the nozzle the more it would be noticeable, so the standard 10N-series parts would show this more.

Here is the CK pyrex short kit on a 26 torch (essentially the same as a 17/18 for the purposes of this discussion) with a wedge collet installed.  You can see how the tungsten is butted-up against one "side" of the orifice.....








...and has a "relief" on the other side.  This is caused by the wedge collet changing the concentricity of the tungsten.






It's not to bad, but you can see how the tip of the tungsten is "off" by about 0.5mm or so.






Is it really that detrimental?  No, in the grand scheme of things, this would not make or break a weld.  Welder skill has a much larger impact than this tiny anomaly.  It could even be advantageous if you "aim" it in the direction of travel, so as to have more argon gas "behind" the arc to protect the weld, but that is splitting hairs. 




In contrast,  standard collet setup, sets the tungsten pretty much dead-center.


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