Oxy/Propane questions...

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Hello all,I'm a newbie here, just found the forum last night! I've had some exposure to welding in the past through my Dad and Uncles. However I moved away from home about 12 years ago and am relearning all of it over again, this time properly! :-)I have a few questions regarding Oxy/Propane. I'm taking a weekend welding class at the local community college, and the instructor there talked about Oxy/Propane last Saturday. I'm looking at getting all set up to do some torch welding/cutting/bending, and have the needed equipment thanks to a generous friend of mine who gave me an older, usable set - minus the tanks of course. I was going to go out and lease a set, but the instructor mentioned that Propane might be the way to go for a home shop like mine. (I'm just a weekend hobbyist...)I need to buy tips for the old Victor torch my buddy gave me, so replacing tips is not an issue. I know from the little bit of info I found on the net that Oxy/Propane uses more oxygen that Oxy/Acetylene, which is not really a huge deal either, considering the amount I will be using my welding setup. I realise also that Propane burns about 1000f cooler than Acetylene, is this a really big deal - other that longer heat up time and less cutting capability? I probably won't be cutting anything thicker than 1/2 inch, or welding anything thicker than 1/4 inch anyway... What about hooking up to the Propane tank? The instructor claims that I can just use the Acetylene regulator screwed right on to the tank, but I think they are both female thread. Is there some kind of adapter available?  Also, how do the pressures compare to those used with traditional Oxy/Acetylene setups - do you just adjust them to the same pressure? Do the gases behave similarly (in terms of lighting the torch and achieving a neutral flame I mean)? How about safety isssues - other than the usual ones present with Acetylene?I read a bit about it on the net, but haven't really been able to find much specific information anywhere (on the net or in any of the 3 or 4 welding manuals I have...) other than a few people saying they had been using it for years instead of Oxy/Acetylene with no problems.Sorry I'm rambling on a bit, but any knowledge or resources you might be able to share with me will be greatly appreciated (especially web sites...).Thanks in advance,French Canadian
Reply:You cannot weld with propane however it is an ideal fuel for flame cutting and is my favourite.As for the regulator fitting a standard 20 pound barbeque tank ... yes is is doable.  You might not be able to directly connect since some acetylene regulators have different/non compatible connections.  You can get an adapter to go from your reg to the propane tank however.
Reply:First, since you mention you have an old torch, the hoses should probably be replaced.  Older O/A hoses are not rated for use with propane, and it can penetrate some hose materials.Second, due to the lower temperature, you can't weld with propane.  Cutting takes a little longer to preheat and reach cutting temperature.  Once you get accustomed to cutting with propane it offers advantages on rusty and multilayered materials.Appreciation Gains You Recognition-
Reply:You will also have to purchase fuel gas cutting tips.  They are of a different construction but most suppliers have them.  If you are near a Princess Auto You might be lucky.   The tips need a bit of care since they are two part.  I use similar pressures to acetylene.  You will have to get used to legating up.  Turn on your gas then lay the torch on a steel plate. Strike up and the flame till remain near the torch tip.  If you don't know this trick you get frustrated lighting up right quick.  It takes a bit to recognize a neutral flame.  The feather is not easy to see.  If in doubt go lean on the flame.  Run the preheats a bit noisy until you gain experience.You will notice that it take considerably longer to preheat your material before you can cut.  The nice thing though is that once your cut has started you will be able to have your torch half an inch off the work and you will not lose the cut.When operated properly will have no slag hanging under your plate on a cut edge.  The cut is significantly cleaner than acetyleneLast edited by lotechman; 03-24-2004 at 12:12 AM.
Reply:You need 'T' or 'M' rated hose.  Most hose is rated 'R' like a good ski movie, or 'RM' which still isn't sufficient.My Acetylene reg does screw right into my 20lb barbque bottle.  Chances are very good that yours does to.  There's an easy way to find out.   Let us know how you like it.Besides preheat, it should cut the same as Acetylene since the Oxy does the cutting anyway.
Reply:I have been using a standard Craftsman (Harris) torch on Propane for 15 or 20 years, with the hoses it came with, with the propane tips, (about $10 to $12 each). It cuts fine. I have never found a propane tank that the regulator would not connect to. The steel I cut does not know the difference between 7500 and 8500 degrees F.  A 20 lb propane tank cuts several times longer than an acetylene tank, can be filled on weekends, does not require a lease, and can be robbed off the grill if I need to finish a job at 10 PM on the 4th of July.  It is a little harder to light in the wind than acetylene, but you will get the hang of it. With the money you save you can maybe build a shop or at least a wind break.
Reply:I'm not sure if I could tell the difference between 7500 and 8500 degrees F.Common sense in an uncommon degree is what the world calls wisdom.
Reply:Originally posted by Brainfarth I'm not sure if I could tell the difference between 7500 and 8500 degrees F.
Reply:I remember running the torch across my palm once.  Didn't need a right glove for a few days since my hand turned to leather.Common sense in an uncommon degree is what the world calls wisdom.
Reply:I prefer acetylene compared to propane even for my home shop.As far as the ability to fill a tank on the weekend you will run out of oxygen sometime too,and the hardware store doesn't fill them.I keep extra full tanks on hand and never run out in the middle of a project. Good luck with whatever fuel you decide to spark up with.
Reply:FrenchCanadian,It all depends on your use, and how much you want to spend. Myself I use propane, but then again I had no intentions of welding with it.  I use it strictly for cutting.  However, it is hot enough if you want to braze.  You can use the same regulators but you will have to change the cutting tips to ones made for propane.  Usually under $20.00.  The propane will seem to last forever compared to the Oxygen.Here in the Great White NorthMosquitoes can't fly at 40 below
Reply:I'm thinking about setting up an adapter for my Oxy reg to use disposable oxygen bottles from Lowe's or HD.
Reply:rusted....now THERE is a lousy idea !   If you're talking about those little red bottles that look like propane cylinders,  I believe you could get maybe 10 minutes out of one...and they cost at least a couple bucks apiece !I'll be the LAST one to let you down !
Reply:I thought the temp difference between Propane and Acetylene is ~ 400ºF? I use propane to cut at school and it works just fine. Ripped out a 1/2" custom wrench last thursday.
Reply:I have cut with acetlylene, MAAP, propane and natural gas.  My choice is propane.   At my presentworksite we use acetylene.  I am living with it but don't like it.  Getting a nice clean cut freehand is more difficult.
Reply:I am totally new to cutting, my son has had several classes in school and knows more than I-except he hasnt done any cutting with propane/oxy...we are about to start a project which requires cutting many (35) cow stanchens out of our barn and some old water pipe... the stanchen are about 21/4 water pipe with solid 13/4 - 2 inch rod for strength inserted into them where we are cutting them at concrete floor.. we have a victor torch head... what size tip should we use and at what pressure settings.. I have tried to find this info for the past hr and half looking thru previous posts but cannot find the answers...any help would be appreciated... [email protected]
Reply:A # 1 oxy/acetylene tip is supposed to cut one inch. A # 2 tip is supposed to cut 2 inches. Seems like I read that an oxy/propane #1 tip cut 7/10 or 3/4 inch. I have never had to cut something thicker, So a #2 NX (Propane tip) should cut 1 1/2 inches. May have to cut it from both sides and whittle it away. I doubt you finding a 3NX without special order. I would start at a 7 lb propane and 40 or 45 lb oxygen. Or you could borrow a Porta-Band band saw.
Reply:I ran acetylene torch cross top of my hand while tyring to keep piece fro tipping over. Trhird degee burn on top of my hand. Wont do that again.Millermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:There are plenty of Victor-style and other brand LP tips on Ebay, which is where I get a lot of mine. If you aren't near a welding supply, tips and hoses can be bought online and I make a habit of checking prices wherever I buy because I'm a cheap bastid.I like #2 tips for general "cutting up scrap", but you can't go wrong with a 0, a 2, and a 3 as a starting selection. Tips are cheap, so even though I go through very few I keep spares on-hand.I use and like both propane and acetylene. Propane is more portable and has no slosh or overdraw issues like acetylene.I ran acetylene torch cross top of my hand while tyring to keep piece fro tipping over. Trhird degee burn on top of my hand. Wont do that again.
Reply:smith torch and propane, then again i dont braze  or weld anything with a torch,btw i get about 7 big oxy bottles to a barbq bottleMM 251MM 135Lincoln Pro cut 55Bobcat 250Miller Thunderbolt ac/dcolder ac forneyJackson nexgen 3n13-Smith OP setups97 Dodge dieselMakita chopsawJet swivel head bandsawlincoln tig 300/30030a spoolgunpuma port. gas air comp.
Reply:Originally Posted by FranzSecond, due to the lower temperature, you can't weld with propane. s.
Reply:If the guy that gave you the equipment had smaller tanks your regulator fitting might look like this. This is a CGA 300 and it will not work with the LP tank..If so, then you will need to get a new fitting. A CGA 510 which looks like this. And if you'll notice how the CAG 300 nipple is cone shaped vs. rounded like the CGA 510. DO NOT use the cone shaped on an LP tank. It will leak, ALOT."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:There is no shielding gas with oxy/acetylene or oxy/propane. The shielding comes from the flux - either coated rod or added flux. You can braze fine with oxy/propane. I never could oxy /propane weld very well but I also can't oxy/acetylene weld worth a flip, so it is hard ot tell.
Reply:Originally Posted by 7mmmagThere is no shielding gas with oxy/acetylene or oxy/propane. The shielding comes from the flux - either coated rod or added flux. You can braze fine with oxy/propane. I never could oxy /propane weld very well but I also can't oxy/acetylene weld worth a flip, so it is hard ot tell.
Reply:For brazing I use flux or flux/coated rods. My welding book defines brazing as "welding with brass or bronze".Yall know this thread is coming up on being a decade old?[Account Abandoned 8/8/16 Please Do Not Attempt Contact Or Expect A Reply]. See you on YouTube! -ChuckE2009
Reply:Originally Posted by lanseyall know this thread is coming up on being a decade old?
Reply:That's why there should be one, sticky, canonical oxy-propane thread.
Reply:Yes, I was suprised to have an e-mail to reply - my previous post was in 2004. I had a hard time remembering my password from that long ago. People are still joining, still needing the info. I thought that was the purpose of the forum.