Soldering wet/dripping pipes

[Lobster]

Had to do some central heating repairs today (a leaking joint) which
involved attaching a new piece of pipework on to an existing 10mm
system. I had hoped to do a soldered joint, but having drained down the
CH and cut off the tube where I needed to, I waited for for the
offending tube to stop dripping water while I assembled the rest of the
new pipework separately.

Still no sign of it stopping completely after about an hour; I was sure
that if I tried soldering to it, I could be pretty sure that the joint
wouldn't take due to an inopportune drop of water arriving. So I went
for an ugly compression joint instead.

How do you get round this when making a soldered joint? I didn't want
to bung up the radiator pipework with bread (as I've seen recommended)
and although I didn't have my wet-and-dry vaccuum cleaner with me (as
I've also seen recommended), I really doubt that would have worked since
I was working at the bottom of a vertical drop from upstairs.

(I'm sure .andy would have had an answer...)

David

 

[A.Lee]

Had to do some central heating repairs today (a leaking joint) which
involved attaching a new piece of pipework on to an existing 10mm
system. I had hoped to do a soldered joint, but having drained down the
CH and cut off the tube where I needed to, I waited for for the
offending tube to stop dripping water while I assembled the rest of the
new pipework separately.

Still no sign of it stopping completely after about an hour; I was sure
that if I tried soldering to it, I could be pretty sure that the joint
wouldn't take due to an inopportune drop of water arriving. So I went
for an ugly compression joint instead.

How do you get round this when making a soldered joint?

I dont think it is possible.
Even if the water is not dripping, I have had it before where the
evaporating steam has built up enough pressure to escape via the still
molten solder.
Nowadys I dry as much as possible, heat up the pipe around 6 or 8"
either side of the joint to dry it out thoroughly, then when cooled
down, and it is still dry, I solder it up.
Where there is clearly visible water that cannot be stopped, I would not
attempt a solder joint.
Alan.

 

[George]

How do you get round this when making a soldered joint? I didn't want to
bung up the radiator pipework with bread (as I've seen recommended) and
although I didn't have my wet-and-dry vaccuum cleaner with me (as I've
also seen recommended), I really doubt that would have worked since I was
working at the bottom of a vertical drop from upstairs.

(I'm sure .andy would have had an answer...)

David

Have a pipe with you that fits over the copper pipe and suck the excess
out,other than that heat the pipe up all the way along to boil off excess
water.

 

[The Natural Philosopher]

Had to do some central heating repairs today (a leaking joint) which
involved attaching a new piece of pipework on to an existing 10mm
system. I had hoped to do a soldered joint, but having drained down the
CH and cut off the tube where I needed to, I waited for for the
offending tube to stop dripping water while I assembled the rest of the
new pipework separately.

Still no sign of it stopping completely after about an hour; I was sure
that if I tried soldering to it, I could be pretty sure that the joint
wouldn't take due to an inopportune drop of water arriving. So I went
for an ugly compression joint instead.

two appraches, maybe three work.

First its important not to try and seal a pipe system that can have
pressure.

Then you can either beaver away with the blowlamp while a nearby tap or
valve steams merrily until the steam has gone, or sometimes pipe freezer
will do the business. That will at least temporarily halt a drip flow.

 

[Dave Liquorice]

How do you get round this when making a soldered joint? I didn't want
to bung up the radiator pipework with bread

Any water about is bad news, either you simply won't be able to get the
pipe hot enough for the solder to flow or the pressure from the steam will
blow it's way out. The former is most likely in your case with a "flow" of
water. Damp will be driven off but even a slow continuous drip is enough
to keep the pipe cool.

I really doubt that would have worked since I was working at the bottom
of a vertical drop from upstairs.

That is the tricky bit any water will find the lowest point. You could try
blowing or sucking the pipe to adjust the level of water further up the
pipe above jiggling and possibly pulling it to bring the end down a bit or
carefully using kitchen roll to blot up the pipe.

 

[John Stumbles]

On Fri, 12 Sep 2008 19:29:27 +0100, Lobster wrote:

....

and although I didn't have my wet-and-dry vaccuum cleaner with me (as
I've also seen recommended), I really doubt that would have worked since
I was working at the bottom of a vertical drop from upstairs.

Sometimes you can get the joint dry long enough to solder by sucking with
your wet & dry vac from another pipe in the system.

 

[Stephen Howard]

Had to do some central heating repairs today (a leaking joint) which
involved attaching a new piece of pipework on to an existing 10mm
system. I had hoped to do a soldered joint, but having drained down the
CH and cut off the tube where I needed to, I waited for for the
offending tube to stop dripping water while I assembled the rest of the
new pipework separately.

Still no sign of it stopping completely after about an hour; I was sure
that if I tried soldering to it, I could be pretty sure that the joint
wouldn't take due to an inopportune drop of water arriving. So I went
for an ugly compression joint instead.

How do you get round this when making a soldered joint? I didn't want
to bung up the radiator pipework with bread (as I've seen recommended)
and although I didn't have my wet-and-dry vaccuum cleaner with me (as
I've also seen recommended), I really doubt that would have worked since
I was working at the bottom of a vertical drop from upstairs.

(I'm sure .andy would have had an answer...)

Use plenty of flux and a large nozzle on your burner. The excess flux
will protect the joint as it reaches soldering temperature and the
large burner will easily cope with the odd drop of water.

If at all possible, solder the lower end of the joint on first before
fitting the higher end to the joint.

Regards,

 

[The Medway Handyman]

Use plenty of flux and a large nozzle on your burner. The excess flux
will protect the joint as it reaches soldering temperature and the
large burner will easily cope with the odd drop of water.

Could you specify what a 'large burner' is & possibly a link to a supplier?I
have a Taymar blow lamp & no way would it ever get hot enough to cope with
even a trace of moisture, let alone the odd drop of water.

 

[The Medway Handyman]

A _real_ plumbers torch thing can make a huge difference. One of my
DIY regrets was not buying one 10 years ago!

Could you suggest a make & model for a 'real' plumbers torch please?

 

[George]

Could you suggest a make & model for a 'real' plumbers torch please?

Taymar blowlamp is crap and a waste of money in terms of buying gas
canisters,get yourself a propane torch.

Great for paint stripping,soldering copper pipes...£10 for a propane
6.5kilo.
http://tinyurl.com/3lus5a

 

[robgraham]

Taymar blowlamp is crap and a waste of money in terms of buying gas
canisters,get yourself a propane torch.

Great for paint stripping,soldering copper pipes...£10 for a propane
6.5kilo.http://tinyurl.com/3lus5a

I'm surprised that no one has mentioned the pipe freezing kit from
Screwfix

http://www.screwfix.com/prods/13369/Plumbing/Pipe-Freezing-Kits/Pipe-Freezing-Kit-220ml

I've used these on couple of occasions and found them excellent.
You'll get 20 to 30 minutes worth of frozen plug out of one tin.

Rob

 

[Stephen Howard]

I've not found this at at all on a pipe which is continually dripping. If
it's simply damp heat will sort that - but this sounds rather more than
that.

It's worked for me - but I did use quite a hefty Sievert nozzle.
I think if it's much more than a drip every couple of seconds then it
might get rather tricky.

I'm wondering whether or not it might be possible to shove a soluble
tablet up the pipe - something like an Alka-Seltzer? Maybe two of them
back-to-back - they'd hold the drips off long enough to allow the
joint to be soldered and then they'd dissolve when the water was
turned on.
Might have to sand them down a bit to get them to fit.

Regards,

 

[Stephen Howard]

Could you specify what a 'large burner' is & possibly a link to a supplier?I
have a Taymar blow lamp & no way would it ever get hot enough to cope with
even a trace of moisture, let alone the odd drop of water.

Well, I can tell you that it's a Sievert as all my soldering kit is
that brand - but as to the nozzle size, it's the second largest one I
have out of half a dozen....and it's about an inch in diameter.
It's a proper gas gun job, with a separate gas supply and hoses etc.
rather than a handheld jobby ( though I've see a few of these with
quite large nozzles before ).

Funnily enough I got that nozzle at the tip - attached to a decent
handle too.

Regards,

 

[geoff]

Taymar blowlamp is crap and a waste of money in terms of buying gas
canisters,get yourself a propane torch.

Great for paint stripping,soldering copper pipes...£10 for a propane
6.5kilo.
http://tinyurl.com/3lus5a

All the real Medway Handymen use a Rothenburger


proper tool for the right job ...

 

[The Medway Handyman]

Taymar blowlamp is crap and a waste of money in terms of buying gas
canisters,get yourself a propane torch.

Great for paint stripping,soldering copper pipes...£10 for a propane
6.5kilo. http://tinyurl.com/3lus5a

Is there a canister alternative though? I'm not a plumber, I just do odd
bits of plumbing. Taymar gas canister lasts me 6 mths +. Dont really want
a bulky 6.5 kilo cylinder on the van either, takes up too much space.

 

[The Medway Handyman]

Could you suggest a make & model for a 'real' plumbers torch please?

Just looking around the SF site, they rate blow torches in watts. The cheap
'peirced can' type torch which looks similar to my Taymar is rated at 250w,
wheras the next one up
http://www.screwfix.com/prods/80471...Hot-Butane-Mixed-Gas/Brass-Torch-Pencil-Flame

is rated at 680w - over twice as powerful. Would that be described as
professional or would I need to go up to a 1200w + version?

 

[A.Lee]

Just looking around the SF site, they rate blow torches in watts. The cheap
'peirced can' type torch which looks similar to my Taymar is rated at 250w,
wheras the next one up
http://www.screwfix.com/prods/80471/Hand-Tools/Plumbing-Tools/Soldering-Br
azing/Brazing/Hot-Butane-Mixed-Gas/Brass-Torch-Pencil-Flame

is rated at 680w - over twice as powerful. Would that be described as
professional or would I need to go up to a 1200w + version?

These are highly rated:
<http://www.transtools.co.uk/store/prod_6883/plumbing-tools/gas-torches/
rothenberger-superfire-2-soldering-and-brazing-gas-torch.html>

Very useful as it can be used upside down, unlike many other torches.

And all the quality plumbing tools here:
<http://www.transtools.co.uk/store/cat_666/_by-brand/rothenberger.html>

Alan.

 

[John Stumbles]

http://www.screwfix.com/prods/80471...Hot-Butane-Mixed-Gas/Brass-Torch-Pencil-Flame

is rated at 680w - over twice as powerful. Would that be described as
professional or would I need to go up to a 1200w + version?

I've got a Bernzomatic. Can't find my model anywhere but I think this must
be the current version of it:
http://www.screwfix.com/prods/94963
But SFX don't sell the gas canisters!

http://www.bernzomatic.eu/torches2.html shows the canister (fitted to a
'pencil torch').

I find this good for up to 28mm and it can deal with very slightly
dripping pipes if you crank it up to full bore (i.e the drips get boiled
off before they can reach the joint).

 

[Chewbacca]

Just looking around the SF site, they rate blow torches in watts. The cheap
'peirced can' type torch which looks similar to my Taymar is rated at 250w,
wheras the next one up
http://www.screwfix.com/prods/80471...Hot-Butane-Mixed-Gas/Brass-Torch-Pencil-Flame

is rated at 680w - over twice as powerful. Would that be described as
professional or would I need to go up to a 1200w + version?

B&Q was selling one of these with a pencil torch and a bottle of gas.
Covers most DIY jobs. Not sure if they still sell them.
http://www.screwfix.com/prods/61690...st-MAPP/Swirl-Flame-Brazing-Torch-JT539T-MAPP

 

[Stephen Howard]

Just looking around the SF site, they rate blow torches in watts. The cheap
'peirced can' type torch which looks similar to my Taymar is rated at 250w,
wheras the next one up
http://www.screwfix.com/prods/80471...Hot-Butane-Mixed-Gas/Brass-Torch-Pencil-Flame

is rated at 680w - over twice as powerful. Would that be described as
professional or would I need to go up to a 1200w + version?

Have a look at the Sievert range - they do a couple of really nice
handheld burners. You can fit a variety of nozzles, and spares are
always available - and the kits just lasts and lasts.
The Turbojet looks interesting.

http://www.sievert.se/sievert_us/turbojet.htm

http://www.gogainindustry.com/promatic/powerjet.htm

Regards,