by Ravvin » Mon May 13, 2019 11:39 am
The only issue I have found with oxy/LPG over oxy/acetylene it the way the oxy/LPG blows the molten metal around.
I bought an oxy/LPG set to use for heating and brazing jobs on a truck restoration. I had 2 large fuel tanks with a row of pits and pinholes where a support strut trapped moisture and I used bronze filler rod to fill and level them. What I found was that once I heated the area and applied the filler rod, the flame pressure blew the molten metal all over the place if I had to reheat an area to keep the filler fluid.
It may be different when doing joints, as you heat the area enough to melt the filler rod, then apply the rod to the join while heating down where you want the metal to flow. Capillary action draws it into the join, so you never actually apply the flame to the molten metal. I just remember oxy/acetylene torches being a much gentler flame.
When I bought the kit, consisting of the 2 regulators, hoses, flash-back preventers, mixer handle, and cutting/brazing/heating tips, it was the same price as the oxy/acetylene kit.
The reason I went with oxy/LPG is that we have a couple of local companies selling welding oxygen, argon and argoshield cylinders with no yearly rental. As long as you take the cylinder back to them for replacement/refilling. The exchange price is actually lower than what you pay at the local BOC place, and you save the $200 a year per cylinder rental.
Of course, about 6 months after I bought the oxy/LPG kit, they started stocking acetylene cylinders under the same scheme.