Soldering - pipes going black

the flame will turn green from a combo of the flux burning and solder, the little mapp gas might not be able to pump enough heat into the 2" pipe, though only trying to weld 1/4 inch should be able to be done.

the pipe turning black is from not getting enough heat into it. be patient it'll take ages to try get the heat in. hold it in one spot for a couple of minutes trying not to move the flame at all.

with the mapp bottles i prefer to solder with 5% rods, they dont need as much heat to run easier

Originally Posted by wozz

the flame will turn green from a combo of the flux burning and solder, the little mapp gas might not be able to pump enough heat into the 2" pipe,

Hi,

He mentioned propane, not MAPP gas. That won't get hot enough for a 5% silver solder joint, especially not with a big 2" pipe to carry away all the heat.

Besides it is not needed.

As it is not subjected to mains pressure like a domestic water service, I'd just use soft solder (tin/lead) for which a propane flame should be adequate. If the small pipe is a neat fit in the hole in the large pipe, that should form a mechanical support for the joint too.

Cheers

true, i just read the bernzo, didnt even see the propane lol.

what colour is the bottle you're using? the yellow, propylene, will burn 100 or so degrees hotter then the blue, propane fuel