The thread on welding problems, prompts my query here.
I have a big a#@ rosebud tip for heating things with my torch. I have real troubles with popping, especially if I have to heat in a corner. Sounds like a machine gun. I've tried all sorts of pressures always with O2 = acetylene pressure. The only way I have any success is to run rich on acetylene which gives a lower temperature.
The popping sound is caused by the fuel-oxy mixture igniting inside the tip. It ignites, goes out, ignites, goes out, etc. etc.
There are a few things that can cause pre ignition. When you are pointing the torch into a corner, the flame may be "rebounding" and hitting the tip. When the tip gets too hot, POP POP POPetc etc. Solution= angle and/or offset the torch so that the flame does not hit your torch.
A dirty or obstructed tip can also cause problems. Use the tip cleaners that you use for the cutting tips.
Last, the gas coming out has to travel as fast as the flame going in (IIRC, about 500 FPS). You need enough pressure and _flow_ for this to work correctly. A full acetylene cylinder can draw more than a near empty one. The draw rate for and acetlyene is 1/7 of the current capacity. I wouldn't even try a large rosebud with a smaller cylinder.
Last, if your tip is too big, you will have trouble with the flow thing, unless you manifold a couple or more acetylene cylinders together. If you need to do this, you need to get a better explanation than I am willing to give here.
I would suggest instead, getting a smaller size rosebud torch. You can do nearly as much, and you won't be going through the gas at the same rate.
I've tried all sorts of pressures always with O2 = acetylene
richer mixture>lower temperature>less chance of pre igntion.
Good advice. Several years ago I got the bug to convert my oxi-acet rig to burn propane. I quickly gave up on this idea when I discovered propane rosebuds are not readily available in most welding supply places and they cost considerably more than the oxi-acet types.