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vmaxnick
01-18-2008, 04:17 PM
This is probably a very stupid thread, but I need information before I blow myself up!
I've already tried once and got away with it and don't want to chance it again!
I am a paintball noob, have just bought markers, filling station and 20oz CA cylinders.
As I understand it, these cylinders must be filled by liquid delivery to the specified weight.
Here comes my dillema: I am a welder by trade and have access to lots of Argonshield light, which is co2 argon mix. I have successfully charged my CA cylinders with pure liquid CO2 from a spare CO2 Fire extinguisher (Siphon tube installed). When I recharge the extinguisher Cylinder from my bulk argonshield tank (gas delivery, no siphon tube) I no longer get a good charge in the CA cylinder. I believe the CA cylinder is now filling with gas rather than liquid and I am unable to reach the target weight before the pressure equalizes. (Now my head hurts!)
So, is the problem that the Argon mix gas will not liquefy in the way that pure CO2 does, or is it because I am filling my siphon tank from a non siphon tank? If this is the problem, can I invert the bulk tank to deliver liquid charge?
I know the simple answer is to rent a liquid delivery CO2 tank but that will cost me a hell of a lot more than my welding gas!
I have to de-cant from my welding bottles to the Fire extinguisher as the welding cylinders do not have siphon tubes fitted and obviously when they are exchanged for full bottles, you don't get the same bottle back (so can't fit a siphon tube to these!)
Sorry this is such a novel but I know there are some really clever peeps on this forum that will have the answer to hand!
Thanks :confused:

IDriveBug
01-18-2008, 04:36 PM
why dont you just order a bottle of CO2 from your welding supplier, its just as common as premix, especially for applications of production welding where pretty isn't needed. That being said, they normally offer siphon or non siphon bottles, but if you dont want to go through that fuss, i dont see why you couldnt put the bottle on its side with the bottom slightly elevated.....

Your less charge with argon stems to the fact that the critical pressure of argon is around 700 psi and CO2 is about 1000psi, therefore you get less expanded volume with similar weights (since their density is close) ALSO, your marker requires more volume of gas at the lower pressures argon mix generates to produce the same velocity.

Cough up the cash, get CO2, your marker and you will be happier

vmaxnick
01-18-2008, 05:01 PM
why dont you just order a bottle of CO2 from your welding supplier, its just as common as premix, especially for applications of production welding where pretty isn't needed. That being said, they normally offer siphon or non siphon bottles, but if you dont want to go through that fuss, i dont see why you couldn't put the bottle on its side with the bottom slightly elevated.....

Your less charge with argon stems to the fact that the critical pressure of argon is around 700 psi and CO2 is about 1000psi, therefore you get less expanded volume with similar weights (since their density is close) ALSO, your marker requires more volume of gas at the lower pressures argon mix generates to produce the same velocity.

Cough up the cash, get CO2, your marker and you will be happier

Sound advice I say. However, I am sort of tacked on to a much bigger firm that uses only argon shield not CO2 and as such I only pay for the gas I use. As they don,t rent CO2, I would have to rent a bottle from the UK's only Supplier who charge extortionate rental, a stupid handling charge just for exchanging the cylinders, and the cost of the gas itself!
If it,s just not possible to use the argon mix, I wont, however if anyone has used argon mix in the CA bottles successfully I would appreciate hearing how you did it and how well it went.
Incidentally, I have managed to get some charge into the CA bottles and they do seem to fire ok, (Dont know how long they will last though) still exhausting plumes of gas vapour so I guess they are full of liquid.
If anyone has managed to use argon mix, could they advise me on the revised filling weights for CA 20oz and 12oz cylinders?
Drivebug, when you say the critical mas of the argon mix, is that the pressure at which argon turns to liquid?
Sorry to be asking stupid question but it's the only way I'll learn!

vmaxnick
01-18-2008, 05:34 PM
Sound advice I say. However, I am sort of tacked on to a much bigger firm that uses only argon shield not CO2 and as such I only pay for the gas I use. As they don,t rent CO2, I would have to rent a bottle from the UK's only Supplier who charge extortionate rental, a stupid handling charge just for exchanging the cylinders, and the cost of the gas itself!
If it,s just not possible to use the argon mix, I wont, however if anyone has used argon mix in the CA bottles successfully I would appreciate hearing how you did it and how well it went.
Incidentally, I have managed to get some charge into the CA bottles and they do seem to fire ok, (Dont know how long they will last though) still exhausting plumes of gas vapour so I guess they are full of liquid.
If anyone has managed to use argon mix, could they advise me on the revised filling weights for CA 20oz and 12oz cylinders?
Drivebug, when you say the critical mas of the argon mix, is that the pressure at which argon turns to liquid?
Sorry to be asking stupid question but it's the only way I'll learn!

I have just found the answer myself; argonshield is NOT argon and CO2, it is argon and AIR! (Oops) so I had better not fill the CA cylinders, I should buy a HPA bottle and use that! :eek:

maniacmechanic
01-18-2008, 05:59 PM
I have just found the answer myself; argonshield is NOT argon and CO2, it is argon and AIR! (Oops) so I had better not fill the CA cylinders, I should buy a HPA bottle and use that! :eek:

now your in a different ballgame ; how much psi is in the argonshield bottle ? the LP HPA bottles are 3000 psi bottles so if you only have 2500 psi in the argonshield bottle you won't get a full fill (but it will be cheap) if say there is 5000 psi in the argonshield bottle you will need a dispensing system (regulator/ expensive)also HPA bottles are much more expensive than co2 bottles

I take it your in the UK , I'm in the US my welding supplier is cool ; I have 2 6000psi nitrogen bottles & 1 diptube co2 bottle , he doesn't charge me any rental on them & sells my gas to me at close to his cost 26$ for co2 & 34$ for nitrogen

punkncat
01-18-2008, 06:34 PM
If the bottles contain liquid CO2 they will be fine. The pressure is not an issue, volume is.

I used to be able to get non siphoned CO2 bottles really cheap as well. I made a bracket out of wood and inverted the bottles to get a good fill. I used a safety chain so the bottle could not fall and damage anything. It was actually quite conveniant as so long as the fill bottle was below the bulk tank it worked really well.
Make sure and get a scale, I am not sure if you mentioned already having one, but it is imperative that you weight the bottle to be sure you are getting a correct and not "over" fill.

vmaxnick
01-18-2008, 07:39 PM
If the bottles contain liquid CO2 they will be fine. The pressure is not an issue, volume is.

I used to be able to get non siphoned CO2 bottles really cheap as well. I made a bracket out of wood and inverted the bottles to get a good fill. I used a safety chain so the bottle could not fall and damage anything. It was actually quite conveniant as so long as the fill bottle was below the bulk tank it worked really well.
Make sure and get a scale, I am not sure if you mentioned already having one, but it is imperative that you weight the bottle to be sure you are getting a correct and not "over" fill.

This gets even more complicated, have just found out that other info about argon and air is wrong, argoshield light is 95% argon 3%CO2 and 2% air according to air products tech sheets
CO2 liquifies at 75 atm or minus 85 f temp (ish) and Ar and O2 at 48 atm or minus 232 f temp (ish) so would that not mean that argon is more suitable for use in marker because a) it liquifies at a lower pressure meaning same volume less weight also less chance of icing in winter weather.
I am convinced that the argoshield will be ok in the marker, but I am concerned for the CA bottles as my weights are way off now, I filled a 12 oz bottle today, it only took about half the 12oz before balancing out with the (full) bulk siphon cylinder, the burst valve did not activate, but the fill station was hissing out gas through all the ptfe taped joints.
I tried the bottle on my marker and velocity seemed fine, I dont know how long it will last though, how many shots should I get from a 12oz bottle (marker is only a Vl charger at present, SORRY!) I know this is a bit risky but hey thats how new ideas are discovered!
Can one of you braniacs work out the charge I should use in the 20oz and 12oz CA bottles from the data on this site: http://www.apithailand.com/carbon.html
Thanks for all your help and suggestions!

vmaxnick
01-18-2008, 07:45 PM
now your in a different ballgame ; how much psi is in the argonshield bottle ? the LP HPA bottles are 3000 psi bottles so if you only have 2500 psi in the argonshield bottle you won't get a full fill (but it will be cheap) if say there is 5000 psi in the argonshield bottle you will need a dispensing system (regulator/ expensive)also HPA bottles are much more expensive than co2 bottles

I take it your in the UK , I'm in the US my welding supplier is cool ; I have 2 6000psi nitrogen bottles & 1 diptube co2 bottle , he doesn't charge me any rental on them & sells my gas to me at close to his cost 26$ for co2 & 34$ for nitrogen

Hi
thanks for your reply, I may still go down this route. I think the argoshield is at 3000psi but see my reply to punkncat for where I've got to so far!
thanks again
Nick

punkncat
01-18-2008, 07:46 PM
The co2 bottles depend on the flash point ofliquid co2 to gas for volume. In essence what you have is a bottle full of pressure that will run out fast.
Good luck with your problem.

vmaxnick
01-18-2008, 07:56 PM
The co2 bottles depend on the flash point ofliquid co2 to gas for volume. In essence what you have is a bottle full of pressure that will run out fast.
Good luck with your problem.
Yea, thats what I thought, I dont understand though why the argon wont liquify at 3000psi
I am using a siphon bulk tank to transfer to the ca bottles!
Could it be because I have not inverted the industrial bottle i decant to the bulk siphon tank from? I wouldn't have thought so, cause this will surely be pressurising the smaller siphon bottle to 3000psi and turning the gas to liquid?? :confused: :confused: :confused: :confused:

vmaxnick
01-24-2008, 06:44 PM
Yea, thats what I thought, I dont understand though why the argon wont liquify at 3000psi
I am using a siphon bulk tank to transfer to the ca bottles!
Could it be because I have not inverted the industrial bottle i decant to the bulk siphon tank from? I wouldn't have thought so, cause this will surely be pressurising the smaller siphon bottle to 3000psi and turning the gas to liquid?? :confused: :confused: :confused: :confused:

In case anyone is interested: Solution!
I now have 3000psi HPA bottles which I fill using a Din air fill station with Argonshield light, the Argonshield light (Argon 95%, CO2 3% Air 2%) is stored at 3300psi and behaves much the same as Nitrogen, as it is very similar in characteristics.
So there you go! Argon is more expensive than most other suitable gasses, but if you have a cheap source like I do, it is suitable. :clap:

So in case anyone else is as stupid as me. Note:

You cannot fill your CO2 Bottles with argon as argon is not stored as a liquid.

So don't try! :nono:

Army
01-25-2008, 12:54 AM
It's not the different gasses you need to worry about, or even volume. It's the burst limit of the tank itself. Co2 bottles have a fairly low burst point, compared to HPA tanks (which, basically, when at normal pressure are above the burst point of most Co2 bottles).

Use Co2 in Co2 bottles, and high pressure in high pressure tanks.

At one AO Day, my 3000psi steel tank was accidently filled to 5000psi. It suffered no damage, and was quickly vented back to 3000psi.

I thank God that it wasn't a Co2 bottle.

vmaxnick
01-25-2008, 05:48 PM
It's not the different gasses you need to worry about, or even volume. It's the burst limit of the tank itself. Co2 bottles have a fairly low burst point, compared to HPA tanks (which, basically, when at normal pressure are above the burst point of most Co2 bottles).

Use Co2 in Co2 bottles, and high pressure in high pressure tanks.

At one AO Day, my 3000psi steel tank was accidently filled to 5000psi. It suffered no damage, and was quickly vented back to 3000psi.

I thank God that it wasn't a Co2 bottle.

Your absolutely right, I am now using 3000psi HPA bottles which I am filling with Argon from my argon bulk tank. Talk about easier than CO2, no purging, no weighing, no loss of gas, a quick release connection on the fill station and my markers love the gas, much quieter but with just as much power. You know exactly how much pressure you have left in the bulk tank and your marker. The best bit; when my bulk bottle becomes too low to sensibly fill the marker, I can carry on welding off the bottle till all the gas is used! Win Win all the way!

I totally recommend argon if you have a cheap supply!

On another point, we've all heard urban myths about what happens when a high pressure cylinder fails? Well the other day I was messing about with a 25liter (Waist high bottle) of siphon delivery CO2 bottle when I accidentally knocked it off the bench, being a fire extinguisher it had no guard around the neck. It landed on the floor and snapped off the valve. The ensuing explosion was deafening and terrifying, followed by my realizing that the cylinder was pin balling around my machine shop powered by the thrust of the escaping gas. I ran like a jackrabbit into the workshop and dove to the floor in front of a customers car. The cylinder managed to shake itself free of the confines of the machine shop, rocketed over my head smashed a hole in the concrete floor then smashed into a motorcycle I had on the ramp before finally running out of gas. If it had hit me, I would be history!
Be warned, Cylinders need to be treated with respect!

:eek: