Propane is what I use in my Oxy/Fuel setup.
Here's my take on Propane...
You can use the same regulator with propane as acetylene... no changes needed.
If using propane, you should get Grade "T" hose... which is for all fuels. Grade "R" hose is for Acetylene only. Why? I don't know... probably some component of the Grade "R" hose degrades with exposure to the petroleum based hydrocarbon fuels. Get the Grade "T" hose. It's a little more expensive, but what you will save by using propane will more than make up for it.
You will need special propane tips to use with your torch. Not a big deal, just go to a welding supply shop, and get them, or have them order them for you if they don't have them in stock. Tractor Supply, Rural King, etc. might have the tips you need also, depending on what brand of torch you have. You
can use acetylene tips with propane, in a pinch... but it is REALLY HARD to get the torch lit. If there is any breeze at all, forget it. But it can be done. Get the propane tips and save yourself the aggravation. Trust me.
Opponents of propane will tell you that you will use more oxygen with propane than acetylene... and technically, they're right. Propane requires more oxygen to burn than acetylene (2.5 to 1 for acetylene vs. 5 to 1 for propane). But, in practice, 95% of your oxygen is used in actual CUTTING (the center hole in the tip)... which is the same for either Propane or Acetylene. In actual use, I think the difference is negligible. The preheat flame doesn't use that much fuel and oxygen. What ever amount more that you will use in preheat is more than made up for by the difference in cost of the fuels. Check into the lease cost of an acetylene cylinder (or even purchase cost for a smaller cylinder) and compare that to what it costs to fill a 20lb propane tank...
That difference will buy a LOT of oxygen.
Opponents of propane will tell you that propane does not burn as hot as acetylene... and they are right. Neutral flame temp of Oxy/Acetylene is 5589 degF, and 4579 degF for Oxy/Propane. What they won't tell you is that Propane puts out nearly 59% more BTU's (1470 BTU's/cubic foot for acetylene, 2498 BTU's/ft3 for Propane) than acetylene, making it a superior fuel for heating/bending jobs.
Opponents of propane will also tell you that it takes longer to start a cut using propane. They are correct, when you use the same technique as you do with acetylene. What most people that don't like propane don't know is that the hottest part of the propane flame is NOT at the tips of the flame cones like it is with acetylene, but about an inch down, in the feather portion of the flame. If you start your preheat with your torch about 1 inch or so above your workpiece so that the edge to be cut is in the hottest portion of the flame (about 1 inch from the flame cones), the greater BTU output of propane makes the preheat time very close to that of acetylene. Once your metal is at temperature, you then lower the torch to the flame cone tips, and cut just as you would with acetylene. So, you do have to adjust your technique just a bit when using propane. Not a big deal, I don't think. I was cutting some 1/2" steel plate and I could start a cut on cold steel with about a 3-4 second preheat with proper technique. That's pretty dang close to acetylene.
Opponents of propane will tell you that propane doesn't cut as smooth as acetylene. I don't know about that... that's really a judgement call when using a handheld torch, and is influenced as much by operator and his prejudices/preferences as it is anything else. I've seen machine cut steel that was cut with propane, and it looked like it was cut with a plasma. Honestly, I dont' think the fuel makes any difference in this area.
You CAN braze with propane. Propane works very nicely for brazing. You cannot WELD with propane. The combustion products of propane work to contaminate the weld puddle, giving a poor weld. But, if you're not gas welding, it doesn't matter.
So... in a nutshell,
Propane is not as "hot" as acetylene... but puts out almost 59% more BTU's... making it better for heating/bending steel. (Temperature and BTU's are not the same thing
)
Propane requires a slightly different preheat technique than acetylene... but once this is learned, the difference between the fuels greatly diminishes.
Propane is MUCH less expensive than acetylene, and much more readily available. Chances are, if you run out of acetylene on a Saturday afternoon/Sunday project, you're out of luck until Monday. With propane, you can borrow the tank off the gas grill, or go down to the supermarket and exchange your tank and you're back in business. Mighty convenient.
A 20lb tank of propane lasts forever. I don't do a tremendous amount of cutting, but I do go through about 3-4 size "M" bottles (about 140CF, IIRC) of Oxygen per year on average. I've had my own Oxy/Propane setup for 3 years now, and I'm still on my first tank of Propane. That's cheap cutting.
So, is Propane Superior to Acetylene? No. But, it does a better job in heating/bending operations because of its greater BTU output (takes less gas to heat the metal to the same temperature) than acetylene. It is not quite as hot as acetylene, and the heat is not quite as concentrated as acetylene. But, with a modification in preheat technique, these differences can be negated. You can braze with propane, but you can't weld with it. Not a real problem these days.
All that said, I really like propane. It works. It's just
different than acetylene, and that's what most people that don't like it, don't like.
Here's a pic of my Oxy/Propane setup...
