CO2 cylinder refill

[Hibbo]

Has anyone had any luck getting a gash cylinder refilled?

I'm sick of using the little disposable gas bottles with the MIG, and have got myself a size B CO2 bottle from the old work's bar. The brewery won't fill it as it wasn't supplied by them, and the local pubs I've tried say the same.

It's a BOC bottle, and when I popped in to the local BOC yard and told the guy I had an empty cylinder and asked if he could fill it he said "certainly not! We will only deal with people who've got an account with us, you've got no right to have a BOC cylinder if you've not got an account with us. All the cylinders belong to us so I'd be grateful if you'd return it to us immediately"
When I told him "Yeah mate, I'll go and get it right now" (whilst advertising Nescafe) he said "Oh we're closing now, you'll have to wait till tomorrow" !

So anyway, where can I get my 7 quid's worth of CO2?

 

[hmang]

you need to get chummy with someone. who has got an account.

 

[television]

Could you transfer some from a larger size, or try your local recycling center.

I got 2 full large cylinders for my brother last year for my local

 

[daveenty]

You need either an independent supplier or possibly a local welding shop.

The local pubs could only swap if the bottle was the same type as their own.

As for BOC, they're technically correct in what they say, as you only buy the gas from them. The bottles are rented.

 

[Apial]

BOC will pursue people for unpaid rental on bottles. They also come under the pressurised vessels safety regulations. Bottles must be checked for safety by BOC to comply with the regulations.

200 bar cylinders could blow up you car if they ruptured. I don't know what a size 2 is, but the cylinders I use weigh 30-75kg and have the ability to go through a wall if mishandled.

 

[Blobcat]

200 bar cylinders could blow up you car if they ruptured. I don't know what a size 2 is, but the cylinders I use weigh 30-75kg and have the ability to go through a wall if mishandled.

Mythbusters did a test on that by shearing the valve off, it is repeated on discovery channel quite regularly and may also be on youtube.

 

[hmang]

Could you transfer some from a larger size, or try your local recycling center.

I got 2 full large cylinders for my brother last year for my local

they call this "decanting" malcolm
the impression i got was its a very very bad idea

 

[Dosco]

Could you transfer some from a larger size, or try your local recycling center.

I got 2 full large cylinders for my brother last year for my local

High risk strategy this

 

[Apial]

Decanting generates very high temperatures as the gas is compressed into the empty cylinder. I would imagine that this is one of the reasons transfilling is not allowed in the UK. Check out this gas cylinder "accident" on You Tube.

http://www.youtube.com/watch?v=rLTK4wsVPjQ

 

[beemerjay]

Find some one who does fire extinguishers

I got a 3 foot tall cylinder costs me about £14 every fill

Mind you cost me £30 for one of their cylinders but thats it it's mine

 

[Dosco]

Decanting generates very high temperatures as the gas is compressed into the empty cylinder. I would imagine that this is one of the reasons transfilling is not allowed in the UK. Check out this gas cylinder "accident" on You Tube.

http://www.youtube.com/watch?v=rLTK4wsVPjQ

When my SCUBA cylinders are fulkeld or even filled they stand them in cold water to keep them cool while recharging from the charging station the recharge is done slowly to manage the risks associated with such an activity.

 

[television]

When my SCUBA cylinders are fulkeld or even filled they stand them in cold water to keep them cool while recharging from the charging station the recharge is done slowly to manage the risks associated with such an activity.

Knowing Hibbo, once he sees that clip he will get new ideas and go off the buttercup and daisy fuel he is working on

 

[Dave's E55 AMG]

Some diving shops do recharge cylinders

 

[Hibbo]

Decanting generates very high temperatures as the gas is compressed into the empty cylinder. I would imagine that this is one of the reasons transfilling is not allowed in the UK. Check out this gas cylinder "accident" on You Tube.

http://www.youtube.com/watch?v=rLTK4wsVPjQ

Knowing Hibbo, once he sees that clip he will get new ideas and go off the buttercup and daisy fuel he is working on

Now that's impressive!

Not quite sure how to incorporate it into a w123 though.

As for the decanting, I understand the heat involved, but I everyday at work I 'decant' 150bar (of nitrogen) from a bottle trolley into the hydraulic accumulators I'm checking, so it's not unheard of.

Thanks for all the tips though, I think fire extinguishing is the way forward...

 

[premmington]

you could use a fire extinguisher (co2) they have the same thread, and can be refilled...

www.remmington.plus.com

BOC Argoshield & Air Products bottles are expensive to hire/exchange (due to bottle rental agreement). Linde Gas will sell you a welding shielding bottle, but outlets are few and far between, unless you live in the midlands, and they cost the earth
You can use CO2 as a shielding gas for Mig welding mild steel but not for stainless steel due to carbon contamination from carbon dioxide (carbon monoxide is created from the heat in the weld pool). Using CO2 as a shielding gas converts MIG welding (metal inert gas) to MAG welding (metal active gas). Active, being the absorption of carbon into weld pool from the carbon monoxide expelled from the heated shielding gas.
Ready source's of bottled CO2 are pub gassing bottles (cellar gas, tavern gas, sureflow). Do not use bottles with nitrogen in them (grey bottles for cream flow beers, Guinness, sureflow mixes). Pub bottles weight 17.25kg when full, 11kg when empty, dimensions are 94cm high x 14cm Ø diameter and they are black in colour (any black bottles marked CO2 with a white stripe down them are for liquid with-drawel and thus no use for welding). £20 is about the going rate for a full pub bottle at the time of writing. Another source of CO2 are 4.7kg Fire Extinguishers. Most fire extinguisher suppliers will refill bottles. Some pubs now use full size CO2 bottles! The size of industrial W-size oxygen, argon/argoshield welding bottles (230bar 85kg gross 146cm high x 23cm Ø diameter).
CO2 bottles show about 50bar (750psi) at 15°C when full and have a 5/8 bsp male threaded fitting. Standard argon bottles have 5/8bsp female fitting designed for a male bullnose fitting. So an adapter or dedicated CO2 regulator is needed (adapter/regulators available from http://weldability.com/ ). Machine Mart sell the cheapest industrial type CO2 regulators.*
CO2 when compressed turns into liquid-ish fluid (thus low bottle pressure, propane/butane & LPG acts very much the same). When contents of the bottle turns from liquid to a gas it lowers in temperature (due to process of gas transfer from a liquid state) thus you may experience some weld splatter as the cold shielding gas hits the red hot weld pool. You can overcome this by fitting a CO2 heater directly threaded to the bottle before the regulator. I use a Murex Sirocco heater but a cheaper version from http://weldability.com/ is available. At very high flow rates (building ships/bridges) CO2 will have to be heated as the low temperatures cause vapor locks and damage to regulators/gas lines. Splatter is also caused by the Arc voltage increasing in CO2, a different type of Mig welding, takes place above <200A in CO2, spray transfer, this has some good side effects i.e. improving weld penetration in really thick plate. If you, can't live with a bit of splatter on thin plate when using 0.6mm wire, you will need Argoshield Lite from BOC, Argoshield Lite also leaves the weld bead with a flatter profile than CO2, which is handy when welding repair patches on cars, saving time on post weld grinding.
Most low amperage (>150A) Mig/Mag welding will need shielding gas supplied to torch at a pressure of1.5-2.0bar (20-30psi) and a volume of 5-7 litres a minute (welding outside in windy conditions will require more gas, about 10 litres a minute and/or physically shielding your welding with a jury rigged windshield, plywood or sheetmetal). A Bobbin Type Flowmeter to set the flow rate between regulator and mig torch is a must for economical usage of gas. It will pay for itself very quickly.
More expensive MIG welders have spot welding timers, one of ours is fitted with this function, I have never used it (total waste of money). You will need a special nozzle shroud with slots in the side of it, to use it anyway. We have two MIG welding sets, a Murex autolynx4 inverter & Miller compact 151 (The Miller being the best of the two, its actually the best portable MIG I have ever used & they cost less than half of the price of a Lincoln, Murex or professional Cebora). Welders with reverse polarity function are handy for using different types of wire i.e. gasless (flux cored). Solid*wire sizes 0.6mm to 0.8mm are needed for all auto repair work. Spools come in 0.5kg 5kg 15kg sizes, 5-15kg size far cheaper if you are going to do any amount of welding.
Alumininium, stainless steel and mig brazing must be done in pure argon.**Helium (balloon gas) can be used for MIG/TIG welding really thick alloys, its messy with lots of splatter, but the weld penetration is very good.

 

[frank133]

gas

hi I know what you mean BOC think they should have the monopoly on gas bottles,I personaly,use tetley and can get them filled at a local motor factors,Its the same bottle they use in the pub,dont you know a friendly pub landlord,failing that most garages have a account with a gas supplier so a local garage could swap a bottle for you,If you live anywhere near merseyside {posh name for Liverpool]I would give you one of my spares.As somone said a fire extinguisher outlet will fill your bottle,they tend to charge more.Have a quick ring around using the yellow pages.But having a BOC bottle limits your options.You could wait till your local pub is getting a delivery,and have a word with the drayman[or nick one when he is not looking]joke?:roll:

 

[Hibbo]

hi I know what you mean BOC think they should have the monopoly on gas bottles,I personaly,use tetley and can get them filled at a local motor factors,Its the same bottle they use in the pub,dont you know a friendly pub landlord,failing that most garages have a account with a gas supplier so a local garage could swap a bottle for you,If you live anywhere near merseyside {posh name for Liverpool]I would give you one of my spares.As somone said a fire extinguisher outlet will fill your bottle,they tend to charge more.Have a quick ring around using the yellow pages.But having a BOC bottle limits your options.You could wait till your local pub is getting a delivery,and have a word with the drayman[or nick one when he is not looking]joke?:roll:

Hi Frank, I've tried a couple of my local boozers, but they both said that the brewery wouldn't take my bottle as they could tell it wasn't one of theirs.

I think I will try some local garages/welding places and see what they say. Incidentally, how much more would it be to get it refilled with Argoshield?

It is a BOC bottle, but I got it from the old work's bar

Thanks for your offer, but I left Birkenhead a while ago and don't go back often!

 

[premmington]

Don't be tempted for "no gas welding wire" all though its improving all the while, its not very good on thin plate & car body work, due to the slag it creates. Its very good for heavy plate (spray transfer <200amps) & when welding outside, the use it was designed for (plus you will need welder that has reverse polarity, gas mig torches are positive, no gas torches are negative). Real high amperage flux cored wire Mig welding above <400amps still use CO2 shielding gas to achieve higher arc voltage & thus deeper weld penatration.

the new Vectra-C model from Vauxhall has been built using galvanised steel plate. By using galvanised steel plate, Vauxhall are offering a longer body life through improved corrosion resistance. This in turn demands the application of new welding techniques, materials and processes in body repair and MIG brazing is a process that is used to braze together galvanised plates using a copper based MIG brazing filler wire (CuSi3) with a low melting temperature >500°C. Thus not removing the original galvanised coating. Spray on, weld thru nickel primer is now available for MIG welding galvanised panels with normal mild steel wire, which improves the rust prevention somewhat at higher temperatures. MIG brazing wire is availible from Machine Mart in 0.5kg or 5kg rolls.

http://www.remmington.plus.com

 

[twistedsanity]

decanting co2 is easy, the only risk is from cold burns if you dont put the connectors on tightly, ive filled hundreds of bottles with nitrous over the last few years, some fire exthinguisher places will refill cylinders with co2 if you ask, just make sure the stamp is in date on the cylinder(10 years)

 

[jamesmc]

Decanting generates very high temperatures as the gas is compressed into the empty cylinder. I would imagine that this is one of the reasons transfilling is not allowed in the UK. Check out this gas cylinder "accident" on You Tube.

http://www.youtube.com/watch?v=rLTK4wsVPjQ

I agree with the above concerning decanting and the heat generated as a result.

Sitting the receiving cylinder in water will help prevent excessive heat build up. We used to do this in the military when filling empty diving cylinders to 200 Bars (which is about 2900 psi).
Regulating the gas transfer to a very slow rate will also help alleviate heat build up.

If you are unfamiliar with handling high pressure gases steer clear.