[matts37chev]

my mixed gas bottle (75/25) for my mig is down to 400psi
when can I consider it empty? how low will it go and still be effective?

I dont want to give away a bunch of gas on my bottle exchange
but i dont want to run out either
I only have one bottle

also has anyone used different ratios?

[stich626]

no idea as far as the psi.. but you could call and find out what the bottle weight is empty..
scale yours and thats the pounds left..
if they can't tell you.. then weight it when it is empty. and use that as a guide, psi can change with temp..
good luck

[matts37chev]

its a small bottle, and its going fast, just watched it drop another 100psi
so off to the airgas store we go (its 25 miles away)

[ogre]

buy another bottle while your there

[454 Rattler]

I ran mine down till the needle didn't move when I opened the valve. It still worked just fine. Makes me wonder if I have a bad gauge.

I took it in cause I was going to town anyway.

Stich626 has a good idea. I should do that too.


454 RATTLER

[Irelands child]

I run mine until I can't hear any hiss when I pull the trigger - or when the weld sound starts to snap and pop. I also just bought a new adjustable regulator instead of a fixed and so far am down to about 15cfh with good welds.

[DanielC]

My welding shop said you can run them to empty.

[Old Fool]

We run them to empty everyday at work.

At home I run 14 for a flow rate, at work it varies with what the welder is doing and if there are drafts.

[matts37chev]

my biggest concern was running out over the weekend

i talked to the guys at airgas about the 84/16 steelmix
they said it would make my life easier on the thin stuff
so thats what I got

did I screw up? anyone else use it?
I remember it was mentioned by someone in a thread a while back

[TexasT]

Is it still a two part ar/co2 ? should be fine. The 'regular' stuff is 75/25. also sold is some ar/helium but I believe it is for stainless. also some ar/ox in different ratios and some three part ar/he/ox for stainless.

Go with what you guy is telling you and see if it works for you and your conditions. Different things for different folks or something like that.

[JohnnyK81]

Run it until nothing comes out.

Think of how much PSI is coming from your welder. Not much at all. DEFINITELY not enough to register on that regulator.