Thread: Converting to LPG and CO2

On the CO2 for MIG front, a bit of hunting about turned up this:
Southern Cross Industrial Supplies - Product Detail: REGULATOR C02 20LPM

Which has a female fitting designed to connect to the male thread on CO2 bottles which is called a AS2473 Type 30 connection.

Not too sure if I can come at $230 for it though...

Originally Posted by JNorton

Hmm...

If you have both TIG and MIG, you get clobbered for two bottles. Argon and Argon / Co2

Wonder if you could just get the Argon off the thieves for the TIG and buy a bottle of Co2... and somehow run a mixer valve to create your Argon Co2 mix for MIG?

Is this feasible or even possible?

Yes, this is possible. There are set ups of this type available, but all the ones I have seen are aimed at large manifold systems rather than the single bottle setup that you would seek.
The big question is why bother?
What do you hope to gain over straight CO2? Presumably you are a home handman welder, therefore you will have little, if any need for spray transfer, (which is a downhand only proposition anyway). The primary advantage that Argon mixes have is the ability to spray transfer, something that few have use for outside heavy fabrication.
For all the mucking around, all that would be achieved is an increase in cost.
To be honest, unless spray transfer is involved I prefer straight CO2 on every count, even for panel work.

So what sources of CO2 are there appart from the ebay types, and is there any advantage in cylinder rental.

cheers

I still rent my cylinder from Air Liquide, same rental a a "G" size argoshield.
The CO2 is much sheaper per litre of gas so there is a definite cost benefit there.
None of us like cylinder rental charges but really they are not too bad considering that you are getting a high grade pressure vessel that will be tested and maintained throughout its life at no extra charge to you.
Cylinder rental is just another operating cost, like your power bill or fuel in ones car.
The alternatives of stick welding or gasless wire are all more expensive per kilogram of weld wetal deposited.

I just went the Ebay route in converting to CO2 on my MIG - I got a 6Kg bottle delivered the next day for $250 and found a C02 regulator at Gasweld for about $95. It's a bit of a fierce arc, but still much more civilised than flux-core and the weld quality seems excellent. Still tweaking the gas flow to try and understand it (mainly so I can tell when I need to turn it up).

You will need 10lpm flow with co2.
I wonder what the fefilling costs will be, as this will be food and beverage grade co2 which will be somewhat more expensive I would imagine then welding grade co2, (I don't know if your refiller will fill it with welding grade co2 either).
Interesting option though.
Once you go to co2 you will not look back to argoshield, (unless you are spraying).

I've started with 10lpm, but am curious to know what to look for when the flow is insufficient as I will be using it outdoors sometimes and will need to know when to bump up the gas flow.

I get the impression none of the welding gas places will even look at a non-rented cyclinder, and I don't think there's any fire extinguisher refillers in the ACT region, so my default choice is the homebrew shop. I'll look into it closer when the time comes to refill.

On the matter of bottle rental.

Don't kid yourself, they have been having a lend of us on cylinder rental for decades.

The rates they charge certainly does not reflect the cost of maintaing a cylinder.

start looking at the cost of owning and servicing things like LPG and scuba cylinders and the industrial gasses just don't compare.

and that is for a cylinder that may be 20, 30 or 40 years old...yeh look at the manufacture dates on some of those cylinders..ever single one has one.

The gass companies have heaps of old cylinders either still in service or recovered since the bean counters realised that not tracking cylinders was the most stupid and lasy thing they could do.

At one stage BOC was picking up abandoned oxy, acetlyne and argoshiled bottles from the Emerald dump by the truck load...play that out all over the country.

Serioulsy......have alook at the manufacture date on any steel argoshield bottle or those old style stumpy E size acetlyene bottles..that is if you can see it under the layers of paint.

Naa mate they are trying to make the money back that thy lost from years of slackness that allowed millions of grey bottles to be out there unrented.

MMM..wasn't it liquid air that originally came to the market with an offer that you could buy a bottle and pay no rent......yeh like that lasted long.

Except from the heavy industrial users they are making more out of us in bottle rent than they do selling us gass.

I note that lots of jewlers are now running oxy / hydrogen of gass generators..........I wonder when someone will come up with a CO2 generator for low volume mig customers....hmmm how about a block of dry ice in a big screwtop jar

cheers

Originally Posted by Karl Robbers

Cylinder rental is just another operating cost, like your power bill or fuel in ones car.

I would agree that for a business that is true, but for the occasional hobby user, rental is over the top.

If I assume one refill a year and bottle rental, it costs me over $200 a year ... as someone has mentioned earlier a 6kg CO2 bottle costs around $250 (probably $275 delivered to where I am).

It takes less than 2 years before I am in front ... sorry, but cylinder rental for the hobbiest is a rip off.

Well this thread couldn't have come at a better time, I just went and looked at the new MIG I'm going to buy soon. I knew the price for gas was expensive but the E size bottles would last me forever and a bit so I was worried about the rental costs. I will definitely look into CO2

Thanks guys this forum always has good stuff

Finding a CO2 regulator was a bit tricky at first - CIG do a very expensive one ($230 as mentioned above), then I found out Lincoln do one for about $106, but when I went to Gasweld to place an order for it, I found a "Toolex" (well, a little Toolex sticker stuck on a very generic Chinese box) brand CO2 regulator on the shelf for $95.

My new CO2 cylinder and reg got delivered today.. got one of these regs

eBay Australia: Buy new & used fashion, electronics & home d

It has an outlet pressure gauge instead of a flow rate gauge but I suspect the only difference is the numbers printed on the front of the dial.

The guy at boc said you can reuse your existing argon regulator if you want and just have to buy a new inlet pipe for the reg to suit the CO2 cylinder, they had them for about 40 bucks as I recall. I didn't want to go that route as I will probably go back to using argon again for specific jobs.

It has an outlet pressure gauge instead of a flow rate gauge but I suspect the only difference is the numbers printed on the front of the dial.

The guy at boc said you can reuse your existing argon regulator if you want and just have to buy a new inlet pipe for the reg to suit the CO2 cylinder, they had them for about 40 bucks as I recall. I didn't want to go that route as I will probably go back to using argon again for specific jobs.[/QUOTE]
As I have posted previously, there is an adaptor that screws BETWEEN your existing argon regulator and your co2 bottle, the last one I bought was around $12.
Yes, I know rent is very profitable for the gas companies, but has anyone here priced a "G" size cylinder lately? They cost in the $1000's, (unlike an lp gas cylinder these are drawn rather than fabricated, excepting acetylene), furthermore, there are relatively few cylinder filling plants, compared to gas retailers, so to refill your own cylinder would be far more tedious than to run an exchange system as is current practice.
There are many facets to this debate.

Yeh one reason why the industrial gass cylinders are so expensive is that you have bucklies of buying one except thu the gas companies, even if you could buy one direct from a manufacturer, you would not expect a good price.

Yes I know the LPG cylinders are very much cheaper to make, an LPG cylinder about the same size as a "D" size industrial cylinder will cost you under $100......

But scuba cylinders are a very reasonable comparison, the construction and preasures are very similar.

The going rate for an 80 cubic foot( free air) dive tank is arround $300 that is breathing air rated and capable of 300bar that would be comparable to a "D" size bottle for any of the comprerssed gasses.

As far as getting the thing filled, well of course there is a problem, the only people who fill industrial gas cylinders are the gas companies, and they will only fill their own rented cylinders.

Its a closed shop Duopoly, and pretty well world wide...Linde and Airliquide controll most of the world industrial gas market.

cheers