Alternatives to Oxy Acetylene

[101RRS]

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/welding/89715-bernzomatic-mapp-oxy-soldering-torch-kit-ox2550tk

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

Thanks

Garry

[p38arover]

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 (https://www.bunnings.com.au/our-range/tools/tool-accessories/welding/industrial-gas-and-accessories)

[pop058]

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/welding/89715-bernzomatic-mapp-oxy-soldering-torch-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.


129680

[cripesamighty]

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!

[Toxic_Avenger]

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).

[JDNSW]

......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!

[Toxic_Avenger]

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!

[101RRS]

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

[pop058]

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.

129710.

[roverrescue]

I picked up a hypertherm xp30
From gumtree a few years back

Freaking life changing For general fabrication/ repairs etc etc!!


My two favourite plasma techniques are

- buy a half sheet of 5mm plate , whack it on your welding bench, when you need a bracket slide it off edge and cut away - voila!

- when repairing / redoing / fixing dial the cut down to 15A or so and you can literally dissolve welds away. So good when say doing Trailer repairs cutting off brackets etc

For heating I concur with MAPP or for really subtle heating I like to grab the rig torch and dial the heat down - with a sharp tung you can literally heat an 8mm nut off a bolt without fubarring the bolt

S

[p38arover]

with a sharp tung you can literally heat an 8mm nut off a bolt without fubarring the bolt

My wife has a sharp "tung". [bigwhistle]

[p38arover]

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.

Working for me.

[101RRS]

Working for me.

Yes thanks Ron - yes it is for me once they fixed it. [bigsmile1]

And thanks for the link.

Garry

[101 Ron]

When I looked at plasma cutters I was doing welding trade courses and was able to try out many different sizes and types.
Get the best plasma cutter you can afford.
Single phase ones with the internal air compressor work OK for small jobs, like cutting the roof off the top of a car..............but not really good for cutting 6 mm plate quickly and cleanly.
I purchased a miller single phase 15amp............top quality thing and never looked back................it will cut cleanly 12 mm plate and much more if I am prepared to go slowly.............the problem was it cost me 4.5 k at the time.
I had problems with tips until I really learnt how to use the thing.
I rarely replace tips now.

[101 Ron]

I ended up swapping over to Oxy /LPG.
The problem is the cost of buying LPG tips and burners/cutters to convert your existing gear to suit.
Core gas supply rent free Oxy/acet bottles and may work out more cost effective.
I think Core gas is the people who supply Bunnings.
With Oxy/LPG you will still need the Oxy bottle .
A normal 9 kg barbeque works Ok for the LPG side of things.
Performance of Oxy/LPG is not much less than Oxy/ acet if the correct tips are used.

[Toxic_Avenger]

I ended up swapping over to Oxy /LPG.
The problem is the cost of buying LPG tips and burners/cutters to convert your existing gear to suit.
Core gas supply rent free Oxy/acet bottles and may work out more cost effective.
I think Core gas is the people who supply Bunnings.
With Oxy/LPG you will still need the Oxy bottle .
A normal 9 kg barbeque works Ok for the LPG side of things.
Performance of Oxy/LPG is not much less than Oxy/ acet if the correct tips are used.

To add to the above...

To convert oxy DA to Oxy LPG, you'd need to consider replacing:
Regulator, Hose, And cutting tips to suit.
You can reuse your old blowpipe, mixer, cutting attachment and flashback arrestors as required.
Details are outlined in AS4839:2001

Oxy LPG is fine for Cutting, heating, brazing, soldering but NOT oxy/fuel welding due to the lower flame temp and higher water content in the combustion process.

Coregas do supply Bunnings. Coregas is owned by Wesfarmers, as is Bunnings, so that's the magic link there. Wesfarmers also own Kleenheat on the west coast, but east coast kleenheat operations and distribution was acquired by Elgas in '15, with some of the business divested to Supagas (owned by Taiyo Nippon- No longer "100% Australian"- their slogan). Interestingly, Elgas (Of BOC / Linde group ownership) supplies the LPG Swap and Go scheme via Bunnings on east coast, deep in the retail heart of the wesfarmers conglomerate. Go figure eh? It's an interesting industry.

Anyhow, the coregas offer is a deposit model with a first fill model, and a refill price thereafter (on an exchange basis).
There are offers with Speedgas (high cyl purchase price- like 400 clams), but offer does not include acetylene.
BOC has a D and G size offer, with included fill for a price per anum.
Power 10 gases (iirc total tools) have an offer as well, but I'm not familiar with it (not in my patch).
Then there is the mail order ebay mobs where you can post (YES, POST!) a cylinder to get filled. Good luck sneaking that past the clerk at the Aus post desk!

TL;DR
Know your usage, know your cyl volumes, and weigh up your options for the work you want to do. ANYTHING is going to be expensive (low perceived value) if you have incur a cost and have no use for it...

[101RRS]

Thanks but that is all overkill for what I need - just the little bottle kits will do me fine though I might change my little propane bottle over to a MAPP bottle and that will do most of what I want where just a bit of heat is concerned and the addition of O2 for a bit of brazing.

As far as the plasma cutter is concerned - this is just a replacement for my angle grinder with a cutting wheel in it so a simple setup is all that is required. Anything more and I pay a welding shop to do what I want.

Thanks for all the options - is great to consider what is available.

Cheers

Garry

[Phil_Seymour]

I am in the process of buying a plasma cutter too. One thing to look for is High Frequency (pilot arc) start, and a torch fitted with a drag cup so you can drag the torch nozzle on the surface you are cutting. If you have a TIG welder, why not use that for brazing. If you don't have a TIG, but do a reasonable amount of brazing then one of the cheaper units will do. There are combi units that will plasma cut and TIG, check Edisons (Welding Machines | Rossi | Available Online at Edisons (https://www.edisons.com.au/construction-diy/welders/welding-machines/)) for a Rossi unit.


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 Buy Mapp/Oxy Soldering Torch Kit OX2550TK | Total Tools (https://www.totaltools.com.au/welding/89715-bernzomatic-mapp-oxy-soldering-torch-kit-ox2550tk)

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

Thanks

Garry