# Forum Home Renovation Metalwork & Welding  O2 concentrators

## boyracer

Anyone used  an O2 concentrator for oxy/acetylene or oxy/propane?

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## familyguy

My guess is that you are looking for a cheaper supply of oxy to get around the highway robbers at BOC or CIG, I went through all of the options including thoughts about making my own acetylene from calcium carbide, after all many years ago workshops had their own acetylene generators. 
My advice is the watch Gumtree for people selling oxy/acetylene welding bottles, they do come up but you need to be quick and be ready to move instantly to go and pick them up as they do not last long. I picked up a set of G sized cylinders (oxy and acetylene 3/4 full according to my gauges) complete with gauges and flash back arresters for $150. G size is really a bit big and not so portable  but at that price I couldn't pass them up. With careful use I should get a few years out of them and no hire fee for the highway robbers

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## Random Username

You can buy the bottles - oxygen + acetylene from Bunnings and a variety of MIG/TIG gasses from a number of other outlets these days. 
For example: Coregas "Trade n Go" Size D Oxygen Gas I/N 5910224 | Bunnings Warehouse

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## boyracer

Hey Familyguy the junkies in your area are far more industrious than where i live...
I saw the Coregas stuff the other day as i left the gate at bunnies. Didn't have time to stop  and enquire though.

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## Marc

You can use medical O2 concentrators for heating, welding but not cutting. Good enough for most applications if you have a spare 3k to buy one. 
The cost will pay for a decade of home use rent and refill. But if you can find one cheap ... why not. You still need argon though. 
However if you think you can make your own argon, I can assure you the risks, and upkeep are not worth it. I looked into it and it is like deciding you want to go buy a horse and a sulky to go to work in the city. 
As far as watching for adds selling O2 or Argon cylinders and then 'move quickly' ... come on guys, are we seriously promoting the purchase of stolen goods? I know a place in Bankstown where you can buy Lotus really cheap ...  
I suppose you can then pump up the O2 in the cylinder with a compressor yourself?

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## familyguy

Who knows maybe the cylinders did fall off the back of a truck, I don't know and I don't feel any guilt, if they do indeed belong to BOC then once they are empty they can have them back. 
I've yet to see oxy/acteylene cylinders at my local Bunnings perhaps when the G cylinders i've got are empty my local Bunnings might have them by then.

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## Marc

So when they are empty you are going to toss them? Well what else, no one is going to refill them that's for sure.
Not very "sustainable" is all I can think of. 
Lets see, I am running low on O2 ... let's check ebay for half full stolen Cylinders... as long as they cost less then half the cost of refilling I am on a winner here ...  :Cry:

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## familyguy

At the rate I use oxy gas I'll more than likely die before they are empty, the E sized cylinders I had lasted me over 10yrs. 
When they are empty and if I 'm still moving I'll take them back to the local BOC highway robbers hideout and drop them off, that's what I did with the last 2 E sized cylinders that I had, they didn't ask any questions just said thanks. In any case we can't be sure they are stolen and I still don't feel any guilt.

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## boyracer

on a related note where did you come across calcium carbide? I can get it in Wollongong in 25kg size bags but thats all i've found.
I have a number of v.old acetylene lamps that i would like to re commission.

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## familyguy

From a company called Chem-supply in Edwardstown I originally picked up a 500g jar for my father in law for just that, a carbide lamp, I didn't go so far as trying to source larger amounts, an acetylene generator (they are still used in third world countries) is messy and in the end I decided that picking up some full or near full bottles from Gumtree was the go, you really need to check a few times a day and move quickly, did have a guy say he would hold them for me until after work, on the way there I called him to find he had sold them to someone else.

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