Disposable gas cylinder thread

[wannabe]

Hi,
Does anyone know what the thread form on the disposable mig gas cylinders is? From what I can see it looks like a M10 x 1 but I'm not sure. I've searched the internet top to bottom but can't find any references to the thread type.
What I am thinking of doing is making up an adaptor to go from the disposable cylinder into the normal regulator. I have the disposable regulator but it doesn't have any gauges whereas the normal regulator I have does so thought it would be good to know what my flow rates was when using the disposable cylinders.

[pipeclay]

Bob the welder has an adaptor for just under $19 plus postage if you dont want to go to the trouble of making your own.

[wannabe]

Hi Pipeclay,
Yeah. I spotted those. Wish I'd spotted one of those 12 months ago. I looked everywhere and couldn't get anything. Ended up having to spending $40 on a disposable cylinder regulator.

Not too sure about the plastic hose connecting the two adaptors together though. Those disposable cylinders are under about 60 bar (870 psi) from what I can figure out. Have serious doubts about a hose under those sorts of pressures.

I've just done search number 1001 and have noticed that in the UK they are saying it's a 1/8" BSP thread. Not sure if the UK standards are the same as Aus though. 1/8" BSP equates to a major dia of 0.3830" (9.728mm). I measured the major dia of the cylinder at very close to 10mm. Normally if you measure an external thread dia you come under the major dia so I'm not sure.

[pipeclay]

Ring one of the suppliers and ask them,dont forget the BSP is tappered not sure where along there length they measure,if you can get a 1/8" cap or reducing bush and check.

[wannabe]

Just an update on these threads for anyone trying to do something similar.
I turned up an adaptor to try things out. The thread on the disposable gas cylinders is 10mm x 1. The thread on the full size regulators is Type 10 which is 5/8 - 14 RH BSP.
These disposable cylinders are expensive but I can't justify the $167 cylinder rental for the amount of use I give it. Another negative on the cylinder rental is that the smallest I can get is an E type which equates to a lifetime of gas and a big bottle to lug around and store.
Been looking at the home brew scene where they use a sodastream CO2 cylinder for their kegging so got myself a gas bottle and made up an adaptor from it to the regulator. The sodastream bottles have a CGA 320 thread. At 330 grams of gas in a bottle (disposables are 390g) and $15 refill at Kmart, Woolies, BigW I'm going to use that option. I know CO2 isn't ideal but for the amount of use I give it, it will do and is about half the cost of disposables.

[silverss]

how do you open the gas on these cylinders when you have it all connected ? ive never used one and im interested in getting one for my mig , also do i need argon co2 to mig weld mild steel or do i just stick with plain argon ?

[johncar]

I believe you will need a mix of Argon and CO2 typically 75/25 or something like that. I Haven't tried it but I have heard that pure Argon doesn't provide the heat for steel and will leave the weld sitting higher and harder to control.
I also have heard that some members on here use pure CO2 with good success at least on medium to heavier steel .
Anyway just found a link to some interesting results for your information..

MIG Welding Gas Comparison