Changing to Propane...

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I have recently changed from acetylene to propane for my torch set-up. What do I set my pressure on for propane???
Reply:Danger ! Danger ! Warning!  Warning ! Will Robinson.This sounds like an accident  just waiting to happen.Acetylene regulators are built to quite different standards  to propane regulatorss and so are the torches and cutting nozzles. The cutting nozzles for propane torches will not fit those of an acetylene torch.Spend some time and do a google search on using acerylene regs for propane, it may save your life!In addittion propane will  only allow you to cut steel but not weld it.The temperatures are high enough for brazing though.More information needed here .How? what? when? and  why type stuff re your torch and  its intended application.Grahame
Reply:I have already done some research, but maybe not enough. I do know that, I have to change hoses, and welding tips. I went to the local welding shop and discussed it with them. But they didn't even know as much as I did. I do have everything hooked up, but I have not sparked any fire yet until I am sure. So, what you are basically sayin g is I need to change everything I have. Regulator, torch barrel, tips, and hoses?
Reply:Originally Posted by lingarnerI have already done some research, but maybe not enough. I do know that, I have to change hoses, and welding tips. I went to the local welding shop and discussed it with them. But they didn't even know as much as I did. I do have everything hooked up, but I have not sparked any fire yet until I am sure. So, what you are basically sayin g is I need to change everything I have. Regulator, torch barrel, tips, and hoses?
Reply:Some guys run up to 10 psi but I never needed more than 5 unless I was burning through heavy plate over an inch thick.Propane is very safe.  It takes a bit of time to learn how to adjust to neutral flame.  I add oxy until the feathers are gone then a bit more oxy to maximise heat.   The greatest thing is that once your cut is started you can have your torch too high and not lose your cut.    Lighting up is a pain.  I tend to open the popane first and get an ugly yellow flame with no smoke.  I then lay the torch close to a metal surface and open the oxygen.  If you don't have the tip down on the metal the oxygen will blow the flame out.  The other way is to open both hand valvels to approximately where you think they should be and light up.  When your torch is the perfect height you will notice that the preheat flames form a series of fingers radiating out form the center.  Too close or too high and the fingers lose their definition.  This is a useful piece of info if you ever end up running a multi-head torch on a burning table.  You can see if your torch heights are correct even if you are ten feet away.  Lastly if you ever switch back to acetylene on your cutting torch make sure you change tips.  Acetylene has a much higher flame speed and it will burn back up into your tip and melt it.  You of course can figure out how I know this.  :'))
Reply:I stad corrected - takes foot from mouth.Maybe its changed now  but 25 years back that was the case in Australia.I have  taken my own advice and did a more thorough search on google and Hobarts says just what Lo tech said.My apologies to you  ,but I would rather apologise than see someone blown up.cheersGrahame
Reply:You can convert your acetylene welding tips into propane tips, you need only to countersink the hole some.  You have to buy special tips for cutting.To light the torch, I light it and turn up the acetylene until the flame moves away from the nozzle and bring it back.  Then, I open the oxygen and bring it to neutral.  I open the acetylene until the flame moves away from the tip, add more oxygen.  I do this 3 times.  The tip should make a whistling noise when you get it right.  If you hold it up against a piece of metal, you should see 2 inch long fingers radiating outwards.The actual pressure you run depends on the tip you are using.  The tips usually come with documentation that specifies a pressure.