I've been using oxy-propylene for a few months now--here's what I've
learned...
I have to change the cutting tips, correct? What about the existing
brazing tips?
I found you can use standard acetylene tips for brazing, but they need
to be *much* larger. I am using a drilled-out #4 to do brazing on
1/8" to 1/4" steel (forgot how big... just kept drilling till it
heated fast enough... I can check if helpful). The little tips blow
out very easily, and the big ones will, too, if I try to braze close
into a 3 sided inside corner, or i/s a tube. I am told if you
countersink the orifice .060 or so it helps keep the flame on the tip.
Also, to get enough heat the torch will hiss loudly. The flame is
not real precise like w/ acetylene, but for most brazing it is fine.
I had no success using an acetylene cutting tip--wouldn't stay
lit--but I think others have done it. I bought a 2 pc. #1 fuel gas
cutting tip and it lights and cuts great.
Like others said, use "T" hoses (which happen to be std on Victor
equipment, I found). Acetylene regulators are fine, unless you are
doing really serious cutting where you might need more than 15psi.
The flux that seemed to be most recommended was Gasflux Type B "Blue
Paste":
http://www.gasflux.com/paste.html
The only authority I could find on flame adjustment is here (for
MAPP):
http://www.machinist.org/army_welding/Ch11.htm
See Figure 11-3 and the text below.
Good luck!
David
(from the link
1. A carburizing flame looks much the same with MAPP gas or acetylene.
It has a yellow feather on the end of the primary cone. Carburizing
flames are obtained with MAPP gas when oxyfuel ratios are around 2.2:1
or lower. Slightly carburizing or "reducing" flames are used to weld
or braze easily oxidized alloys such as aluminum.
2. As oxygen is increased, or the fuel is turned down, the carburizing
feather pulls off and disappears. When the feather disappears, the
oxyfuel ratio is about 2.3:1. The inner flame is a very deep blue.
This is the neutral MAPP gas flame for welding, shown in figure 11-3.
The flame remains neutral up to about 2.5:1 oxygen-to-fuel ratio.
3. Increasing the oxygen flame produces a lighter blue flame, a longer
inner cone, and a louder burning sound. This is an oxidizing MAPP gas
flare. An operator experience with acetylene will immediately adjust
the MAPP gas flame to look like the short, intense blue flame typical
of the neutral acetylene flame setting. What will be produced,
however, is a typical oxidizing MAPP gas flame. With certain
exceptions such as welding or brazing copper and copper alloys, an
oxidizing flame is the worst possible flame setting, whatever the fuel
gas used. The neutral flame is the principle setting for welding or
brazing steel. A neutral MAPP gas flame has a primary flame cone abut
1-1/2 to 2 times as long as the primary acetylene flame cone.