I am not getting a puddle or penetration with my MIG!

"How does that mix exist in a single cylinder? Pure CO2 is gas over liquid. "

In this case the CO2 is compressed (with the Argon) instead of liquified.

Dave

Reply to
spamTHISbrp
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I don't do production welding. A bottle of Ag25 lasts me quite a while.

Reply to
Don Foreman

According to the physics books, it all depends on the partial pressures of the gasses in the bottle. This is the pressure that would exist if that amount of that gas were all that was in the bottle. So, for instance, the partial pressure of CO2 in a 75/25 bottle filled to 3000psi would be 3000 x 25% =

750psi, which is a bit less than the saturation pressure of CO2 at room temperature of about 800psi. If you took such a bottle 'up north' and used it outside, you might find that the mixture was argon rich due to liquefaction of some of the CO2 until the bottle pressure had dropped a bit. The mixture would be right at about 400psi at -20F for a 75/25 bottle according to the phase diagram I just found.

Anyone want to give an answer based on fact and experience, rather than supposition? :-)

Mark Rand RTFM

Reply to
Mark Rand

OK, I'll be verbose: Ag is silver, argon is Ar. :-))

Nick

Reply to
Nick Müller

OK, that makes sense. I was thinking it was 75 percent CO2.

Reply to
Richard J Kinch

No wonder the stuff is so pricey! They really do call it Ag25, at least at the welding store I buy it from.

Reply to
Don Foreman

Silver solder gas ?!

Martin Martin Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net NRA LOH & Endowment Member NRA Second Amendment Task Force Charter Founder

D>

Reply to
Martin H. Eastburn

welllll....not really. Burns hot and deep. Does splatter a bit though.

99.99% of my Mig welding is with C02. If I want to make it pretty and in clean steel, Ill hook up a tank of C25..but for the rusty old shit I use around the homestead..Co2 works hunky dory

Gunner

"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."

- Proverbs 22:3

Reply to
Gunner

I have done this test and am filling a 1/2 litre bag in 3-4 seconds.. So I am using approx 9-10 litres per minute!! Is this too much?

Jon

Reply to
jon.p.weaver

15-25 cubic Feet per hour is about normal. I suspect you are running a bit much gas....

Gunner

"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."

- Proverbs 22:3

Reply to
Gunner

That's approx 20 cubic ft/hr, about right.

Ned Simmons

Reply to
Ned Simmons

If anything I am using less than that.. Although my maths could be suspect... Here is my rational (And this could be flawed from the start).

- 1/2 Litre measures approx 3x3x3 inches, so there are 64 1/2 litres in a Cubic Foot.

- If I am using 1/2l in 3-4 seconds, then this equates to 1cft approx

200-250 seconds.

- There are 3600s in one hour, so this equates to 14-18 cft per hour.

So, if my maths is right, could I be using to little gas?

Jon

Reply to
jon.p.weaver

Hi Jon,

I guessing from your addy that you are in the UK. I don't know for sure what voltage your machine is, but have you checked that? For instance are you using an extension cord or anything else that could be causing a voltage sag/drop along the way to your welder?

Turning up the output on the welder won't work if you can't supply it enough juice to handle the increased output.

Just one more possibility...

Reply to
Leon Fisk

It could be a bit more 10..12 liters is OK. The rule is: wire diameter (in mm) times 10 + 2 = liters / minute of gas. Assuming a 0.8mm wire, 10 liters are OK. And yes, it can be a little less.

Nick

Reply to
Nick Müller

The math is ok..so is the actual gas use. Still sounds like reversed polarity to me..might want to swap em and see if it works better.

Gunner

"A prudent man foresees the difficulties ahead and prepares for them; the simpleton goes blindly on and suffers the consequences."

- Proverbs 22:3

Reply to
Gunner

10 liters/min is 21.19 cu ft / hr. That should be OK.
Reply to
Don Foreman

Flux core runs hotter than solid wire with gas. You need to turn up the voltage.

Reply to
Don Foreman

3.785 L/gal * 7.48 gal/ft^3 = 24.31 L/ft^3

Pete Keillor

Reply to
Pete Keillor

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