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Jeff Wisnia Jeff Wisnia is offline
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Default Having trouble soldering copper pipe

wrote:

On Oct 23, 8:33 am, Jeff Wisnia wrote:


At the risk of telling things you probably already know and are doing.......



That's okay, I should have explained what I was already doing better
anyway.


Are you SURE there's no water left in the pipes which is somehow keeping
the pipe from getting up to soldering temperature?



Yes, at least on most of my attempts I've been removing the elbow
completely (and replacing it with a new one) so I can see down the
supply end of the pipe and no water is anywhere near the top. A
couple times (I mentioned I made a LOT of attempts), when I tried to
just fix the minor leak by adding more solder, there may have been
some water those times... but I've tried both.


Are you cleaning the INSIDE of the part of the elbows which fit over the
pipe ends, using a wire brush or abrasive cloth until they are bright
and shiny copper?



Yes, with a wire brush, that 4-in-1 tool made for the job. I don't
spend a hole lot of time on the inside of the elbows though, because
they are brand-new and already really shiny. I just insert the wire
brush and maybe 6 or 8 twists... I then use toilet paper or paper
towel (I've tried both because I'm not positive, but I don't think
either have any "oils" or perfumes in them, which I know would be a
bad thing) to remove any oil and/or dust.


Are you using a decent paste flux wiped onto the pipe ends and the
inside the elbows?



Yes, "paste" flux. I do notice that it runs down the pipe most of the
time, when I start to heat the elbow. Mostly on the end of the elbow
pointing downwards, which I imagine isn't ideal, but I'm not sure how
to avoid this. I was using too much flux at first, but now I just put
a thin coat on.


Heating in the middle is not necessarily the best way to do it, you
should probably move the flame from one side of the elbow to the other
while heating if you're going to solder both ends "at once"



I think I'll try doing one end at a time again. It wasn't working
very well, I think, because I was applying the heat around the middle
of the elbow. I was worried that applying the heat to close to the
end of the elbow, may heat the pipe faster than the fitting, or not
heat the fitting far enough inside so I may only get solder around the
edge.


Other than that, I can't think of why you're having problems with one
elbow unless someone's put a curse on your plumbing.



Thanks Jeff. Could be.




I'm leaning toward your not getting the elbow and pipe hot enough before
you apply the solder. You should be anble to see the molten solder suck
into the joint through capillary attraction and flow around the
circumference of the end of the fitting if things are going right.

Is the elbow located in a restricted position where you can't get the
torch flame very far "around it? If so, sticking a piece of sheet metal
an inch or so behind the joint can help "reflect" some of the torch's
heat to that side of the fitting.

Keep trying, it's not rocket surgery, and you can only succeed as far as
you dare to fail.


One other thing that is going to keep me up at night... is there any
way to really know if you made a good solder? If it doesn't leak
after a couple days, could it still be a "bad" connection and start to
leak after a couple years? I know any connection could leak after a
couple years for various reasons, so maybe the question doesn't really
have the kind of answer I'm looking for.... what I really want to
know, is how can anyone be sure that they did a good job.
Unfortunately, based on past experiences, hiring a professional
doesn't give me any more peice of mind, again, unless I had some way
to check their work, but then I could just use that same method to
check my work (and only call a pro if I couldn't get it right). I
guess the only plus with hiring someone else, is that I have someone
to sue, but I probably wouldn't bother sueing anyway, so guess that
doesn't matter for me.




Hydraulic (water) pressure testing of plumbing systems is done, but
usually only on new construction. I've never heard of a plumber doing a
"repair" job on something in a home doing that, but if you want to learn
a little more about it look he

http://tinyurl.com/yopt2w

The only time I ever experienced a soldered copper fitting "blow right
off" was nearly 50 years ago a couple of months after I'd moved into a
basement apartment in a brand new building. An elbow blew off in the
kitchen of the apartment above mine in the middle of the night. My
neighbor noticed water running out from under my entry door in the
morning and woke me. What a MESS. Being a bachelor, my kitchen cabinets
held more than just food, and I lost a few things I wish I still had,
among them a 1940's Contax 35mm camera with "Geheime Staatspolizei"
(Gestapo) engraved on its back, brought back from WWII by a returning
GI. My tenant's insurance paid me a decent amount for it, with the
condition that they got to keep it.

Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.