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Plumbing in the Home/Resoldering copper into a brass fitting? Help!


THANKS MUCH for the reply!  You provided some info that I had not seen anywhere before...was wondering, however...when i did my other joints before, the flux began bubbling LONG (2-3 min) before any solder would this normal when using a propane torch? I'm using the Bernz-omatic(?) economy kit from H/D...

And how much difference would it make if I had bought a MAPP torch? I understand that is a bit hotter...
Followup To
Question -
I have just found this site...have done only two solder joints (drains) thus far...using std propane torch...have a lav drain pipe that I need to reconnect back into existing brass 1 1/2 inch fitting...the brass connector is in location under house that is quite inaccessable...only one side easy to get to...old joint was 55 yrs old and a real pain to get apart...took about 10 min with torch...there appears to be some old solder left inside should I best handle this job? THANKS!
Answer -
The secret  of soldering is cleaning, fluxing and heat.
As you explain, the lav pipe is 1 1/2" copper that you wish to solder into a brass fitting that still has residue solder left in the fitting.
First you must heat the fitting up to where the solder melts. Then, while its still liquid, take a dry rag and wipe all the excess solder out. ALL OUT!!! You will be left with a  silver finish on the brass but should be able to slip a pipe into the fitting.
Now take plumbers sand cloth and shine the pipe back a few inches and with a 1 1/2" cleaning brush shine the inside of the fitting.
Now paint both pipe and fitting with NoCorrode Solder paste or a acid based paste and join the pipes.
Fire up the torch using a medium tip and apply heat to the the BOTTOM of the fitting while holding the tip of your solder on TOP.
When the solder begins to melt on top run the tip of the solder around the joint.  Capillary action will suck the solder into the joint as you run the solder around the joint. Run the solder around several times and let it set it.  You have just completed your solder job.  Hope this helps and thank you for rating my reply.  Tom

The flux will melt long before the solder but not to worry its doing its job.  I piped a entire house using a Bernsamatic torch.  A mapp gas or acetylene torch will give out a hotter flame then propane but unless you plan on running a lot of copper your torch will be just fine.  Good look and thanks for the rate and the kind words.  Tom

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