Acetylene vs. Propane

[lingarner]

I recently changed from acetylene to propane torch, and I used it for the first time today. Also, it was wind 5-10 mph. And it sucked. even if there were no wind, I still wouldnt like it. I am already planning to go back to acetylene. Any of you feel the same about propane?

I will keep paying for the more expensive gas...

[denrep]

Originally Posted by lingarner

...changed to propane torch, and I used it for the first time today. Also, it was wind 5-10 mph. And it sucked. even if there were no wind, I still wouldnt like it. I am already planning to go back to acetylene. Any of you feel the same about propane?...

I love propane.

Wind should be irrelevant.
You may have to relearn your torch lighting technique.

Lay the tip against your work while you alternately add fuel and oxygen to get a nice flame.

[TozziWelding]

I run Propylene(MAPP) gas which is very simalar to propane(I run propane on my other set of torches with the same tips). Once you learn how to light the torch in the wind you will be all set. All you need to do is crack the gas, AND oxygen valves, then strike it. I won't ever switch back to dinosaur gas(acetylene), no tank lease on MAPP/propane, can run over 15 PSI, heats better, Propane is cheap(so am I), you can run off a BBQ tank(also cheap), and no "little witches" flying around when you light the torch. Just my 2 cents, either you love it or you hate it.

[76GMC1500]

If you don't weld with your gas torch, you'd be almost stupid to use acetylene.

[MAC702]

I assume you had propane tips?

[tapwelder]

I really like propane.

I went through the same feeling when I started with propane after switching from acetylene.

I really cuts well, last much longer and is safer. I haven't noticed any increased consumptions of oxygen.

Most large cutting companies around here use fuels other than acetylene.

As Mac suggested, are you set up properly to run propane?

[lingarner]

Yea, you guys sound right. I had just tried it today, and noticed that I cannot turn the gas on as much as acetylene. It was really foreign to me. But seeing all you guys using it, I am sure there is a reason.
What do I need to set my regulator on for propane?

[denrep]

Originally Posted by lingarner

... noticed that I cannot turn the gas on as much as acetylene...

What do I need to set my regulator on for propane?

Actually you can run higher flow and pressure than with acetylene, however you will have to raise it progresively by alternately adding propane and oxygen to your start up flame.

Or, hold your tip near a plate, so that the "wild" propane flame is somewhat concentrated and redirected, slowly add oxygen until the flame jumps back to burn just off tip.

15 psi should be a good starting point.

[76GMC1500]

The trick I use when lighting a propane torch is to light it, open the fuel until the flame moves away from the tip, bring it back to the tip and then use the oxygen to bring it to neutral. Open the fuel until the flame moves away again, bring to neutral. Do this one more time. When you get the flame right, it will whistle some. If bring the flame down on to a metal plate, you should see orange fingers about 2 inches long radiating outwards if the flmae is set up properly. Once you get the hang of propane, you'll never go back.

[David R]

A propane tip helps a whole bunch. I do a lot of cutting and acet is hotter, so I use that. If I have a big preheat job with the rosebud out comes the propane.

David

[tapwelder]

Cutting tips need to be replaced. Also, hoses need to be replace to run propane.

Porpane provides more than enough heat to cut metal. Heat does not do the cutting, oxygen does the cutting.

This topic came up several months ago. I thought acetylene was the norm. I have been using propane several years, now. However, after several post and some local inquiries I found many people use fuels other than acetylene. Some local large operations use natural gas and chemolene. These companies run cnc tables all day long and cut 5+ inches thick.

[hywyh8r]

Natural gas? Could this be done with an ordinary cutting torch? Since I already have NG in my garage Could I T into the line and run it to the torch regulator? I really don't see why not since all I had to do to make my BBQ from propane to NG is drill the jets slightly larger. And NG is cheaper still than propane and you never run out.

[KMAC]

Originally Posted by hywyh8r

Natural gas? Could this be done with an ordinary cutting torch? Since I already have NG in my garage Could I T into the line and run it to the torch regulator? I really don't see why not since all I had to do to make my BBQ from propane to NG is drill the jets slightly larger. And NG is cheaper still than propane and you never run out.

The natural gas in your garage is regulated to 3.5" water column (less than one psi) so you would have to buy a pressure booster. Unless do a s--- load of gas work it wouldn't pay for itself.
As for the propane/acet thing I've used both and the propane is fine but I use acet out of habit and laziness to switch over. I will look into changing over when I stop being a procrastinator.

[Doolittle]

I will allways use acetelyn for my stuff, but using the rosebuds with propane sounds like a good idea.

[David R]

It seems to take forever to preheat for a cut in heavy steel with Propane. I have the proper tips too.

David

[zapster]

Also, hoses need to be replace to run propane.

Ummmmmmmmmmm...NO..
You can use any fuel / accelerant hose set for it..They're all the same..Threads and all..
I just replaced ours a few months ago with standard 'ol stuff..

...zap!

[zapster]

Originally Posted by David R

It seems to take forever to preheat for a cut in heavy steel with Propane. I have the proper tips too.

David

Well you must be doing something wrong then..
We use Propane Oxy set up to heat anything we do that has to do with shrink fit..
Ane we do big stuff..
I cant see where pre-heat for cutting and what we use it for has any diffrence..

Propane is far and away the better gas for heat in those situations..
Very rare that we use Accetelyne for anything to do with all out heat now-a-daze...

...zap!

[DirtyLittleSecret]

This is why I love this site!

[zapster]

Originally Posted by DirtyLittleSecret

This is why I love this site!

Thats exactly right..
All the diffrent angles are exposed...

...zap!

[littlefuzz]

Originally Posted by David R

It seems to take forever to preheat for a cut in heavy steel with Propane. I have the proper tips too.

David

Maybe you need a bigger torch to do what you want. I use propane at work and acetylene at home. The torch at work heats a lot faster than mine at home cause it's bigger. Flows more gas, thus more heat

Originally Posted by tapwelder

Cutting tips need to be replaced. Also, hoses need to be replace to run propane.
Porpane provides more than enough heat to cut metal. Heat does not do the cutting, oxygen does the cutting.

I'll agree with the tips but have never heard of anyone replacing the hoses to swap over to propane. And what do ya mean "heat doesn't do the cutting", if ya didn't need heat we'd run straight Oxygen.

[tapwelder]

It is my understanding that oxygen is an oxidizer. It causes things to burn. The heat brings the metal to a certain temperature, then the straight oxygen from your jet causes the metal to oxidize rapidly. Clean jet = clean kerf

You can actually turn your flame off after cutting starts (keep oxy lever depressed) and the torch will continue to cut for a while. Try it. Eventually it will stop cutting because the metal cool.

If you just apply straight heat not much cutting occurs just a molten mess.

My initial point was -it doesn't matter what fuel you choose to get the metal hot the oxygen does the cutting.

There is a propane grade hose. I didn't change my hoses out either. However, propane degrades acetylene hoses.

[denrep]

Originally Posted by littlefuzz

... have never heard of anyone replacing the hoses to swap over to propane...

From the horse's mouth at: http://www.weldingmag.com/323/Issue/...se/45963/Issue

"...fuel gas other than acetylene requires the use of Grade T hose to ensure compatibility with the gas being conveyed, and user safety. Even if using acetylene, Grade T hose provides additional features and benefits..."


We can review "gasless" cutting at:Post 40 http://www.weldingweb.com/showthread.php?t=8867&page=2

[littlefuzz]

Well guys I am humbled once again, it goes to show you never quit learning

[Diehard]

probably a dumb question but if you switched to propane, what size tip would you need? i mostly cut 1/2 inch and smaller metal.

[76GMC1500]

If you use a Smith setup, a 0 or even a 00 tip will cut half inch just fine. It's a common mistake to use too large of a tip and even the small ones will cut some thick stuff. The 00 is recommended for materials up to 1/4" thick, but will cut up to 1" thick.

For the degredation of hose, your acetylene hoses which normally last 5-7 years may only last 3-5 years with propane. Don't worry about replacing them until they actully wear out, then you can get the more expensive T grade hose.