Thread: Alternatives to Oxy Acetylene

You could always get the low cost oxy/acetylene bottles from Bunnings. Deposit required bu no annual rent.

Industrial Gas & Accessories available from Bunnings Warehouse

Originally Posted by garrycol

My old axy acetylene bottles are just about empty and I am going to get rid of them. I really didnt use them much - mainly for when all else failed for both cutting steel and heating metal and brazing.

For cutting I like the idea of getting a basic domestic grade plasma cutter that uses compressed air - probably wont need to cut more than about 5-10 mm.

For brazing and heating to free stuff up where a normal propane torch does not provide enough heat I was thinking of one of these https://www.totaltools.com.au/weldin...h-kit-ox2550tk

So recommendations on a plasma cutter and how the propane/oxy kits work.

Thanks

Garry

I have one of these. It struggles but will cut 10mm although not cleanly. It was as big as I could go and stay with a 10A plug.
I also have separate compressor with a toilet roll style filter. Clean dry air is the key.


plasma cutter.jpg

Garry, a friend of mine carried the Autobarn equivalent of the totaltools oxy kit in his 4WD. Problem for him was the only time he had to use it in the bush for a repair, the bottles ran out really quickly. Since your usage is low, if you do end up buying one, get extra bottles, just in case!

As others have said, clean dry air for plasma is key. Otherwise you'll be burning thru tips, electrodes and shield cups like nothing else.
If you get a cheapie with internal air and don't mind voiding the old warranty by dismantling it, intercept the internal air source (pretty much a small 240V compressor), and rig in some nitto fittings to a larger, external water trap/filter. Many don't have this functionality out of the box.

As for heating the old rusted nut etc... just go MAPP. I honestly don't see how much more than red hot you'd want to go for that application- if your plasma is there for cutting.
For oxy/MAPP, then keep in mind the oxy/fuel ratio - 5:1... so enjoy paying thru the nose for the little cylinders. As a point of reference, oxy:acet is approx 1:1. Oxy:LPG approx 1:4. Acetylene is the fuel gas of choice IF you have a need for it- Highest energy content by far due to the triple bond between carbon molecules (it's chemical composition CH4).

Originally Posted by Toxic_Avenger

......Acetylene is the fuel gas of choice IF you have a need for it- Highest energy content by far due to the triple bond between carbon molecules (it's chemical composition CH4).

May have changed since I did university chemistry, but last time I looked, CH4 was methane, and acetylene was C2H2!

Originally Posted by JDNSW

May have changed since I did university chemistry, but last time I looked, CH4 was methane, and acetylene was C2H2!

You are 100% correct. I was getting all hot under the collar on stoichiometric ratios, I forgot a carbon atom!

Thanks for all that advice - great stuff - I have a full size compressor (17cf) with water trap etc so should be OK for the basic plasma cutter. Sick of using an angle grinder.

Yes I appreciate the o2 use with the MAPP set - the site I linked too says the Usage Ratio: 1 X Map Gas to 5 X Bottles of Oxygen and Oxygen will last 10 minutes on high flame. I have just the basic propane bottle at the moment so I might upgrade it to a MAPP for general heating etc and just use the O2 for those special occasions.

Ron - when I click on your link to Bunnings it says the site is down for maintenance so I will check it when it is back up.

Cheers

Garry

Garry,

The "normal" water trap are not upto the task for plasma IMHO and not real good for trapping particles. This is the one have and not a lot of money (compared to the plasma). Less than $100.

air filter.gif.