Soldering in tight places

[Ian Gills]

This weekend I intend to correct a mistake I made before I learnt how to solder.

I attached a compression quarter-turn angle stop on the cold water line to the kitchen sink but had to cut the copper pipe very close to the wall. This could make life tricky if the stop ever needs to be replaced and the compression fitting cannot be undone. The pipes are under the sink in a cupboard.

I will remove the stop, and solder some extra pipe using a coupling and then replace the stop with a new compression fitting. I have a heat shield (which I recently used when soldering near the wooden joists in the basement) and will use this again. But are there any other tips when soldering in tight spaces?

I am going to do as much of the soldering out of the cupboard as I can (one half of the coupling, maybe a 90 as well) and only use the minimum amount of heat and solder when in the cupboard. Anything else I should consider?

Many thanks.

PS. Yes I have a fire extinguisher and will keep it handy!

[jadnashua]

They make ferrule pullers, so you should always have a way to get that off. If you don't like the short stub, you could consider just soldering on a male threaded fitting, then using a threaded valve to it. It would lengthen the stub, and then you wouldn't have to worry about a ferrule getting stuck. Consider a brass fitting rather than copper...it's getting harder to find decent threads on the copper stuff (although they are out there, but maybe not at the big box stores).

[Ian Gills]

Genius! Thank you. I adore the threaded valves (I have them in my bathroom). Ten years on, they came off a breeze and they seem to fit better than compression.

I shall do as you say and go for brass (which I love to solder).

Thank you.

[hj]

If you can get the valve off to solder the extension on now, then you will be able to get it off years from now, if it is necessary. But even then all that is usually necessary is to unscrew the nut, remove the valve, and then tighten the existing nut back onto the new valve, because you will not have the valve/nut mismatch that would require changing the nut.

[Ian Gills]

Are you sure these fittings do not "fur up" HJ? The ones I recently replaced (leaking, 11 years old, and leading to my current "problem") had to be cut off. The nuts would not come undone without damaging the pipe. Perhaps they had been glued or simply overtightened. I dunno.

But if any more cutting is needed down the road, then I will be in trouble with the pipe already so close to the wall.

[Terry]

Shutoffs normally last a good 20 years.

We use sleeve pullers to get the back nut off.
We must replace a dozen a week that way.

If worst comes to worst, you can always cut a bit of drywall back in 20 years to bury the back nut.

I personally don't like soldering under cabinets near the wall. I would much rather use compression fittings.

[frenchie]

Hold on - you're doing this just because you want to avoid problems later? The valve is still okay?

It's no easier now than later.

Unto each day is sufficient the evil thereof, and all that.

Go for a walk in the woods, or take up sailing, or spend some time with a child, or something. You've got too much time on your hands.

[hj]

IF you could not remove the nut from an old valve and had to cut it off, you were using the wrong wrench. I have NEVER had it happen.

[Ian Gills]

Frenchie, plumbing is a hobby. Something to be enjoyed. And an artform. I don't see why anyone would need (sorry, want) to get paid for it. You like the smell of WD40. I like the look of freshly fluxed copper.

Now, being stuck in an office all day. That is a real bind! I could happily plumb all day.

I am also worried that where one compression valve is, it might get knocked or pulled off.

HJ, I do not believe you. Even after I cut the pipe, I though I would wrench the nut for fun. Did it move? Nope.

And thank you Terry. Your advice is very sensible.

[tjbaudio]

If it is not leaking it is not broken. Leave it till it is leaking or broken. The problem you had with the first one was probably due to the initial install fitting having a damaged thread or being the wrong size or some thing like that. Changing it now just because you had one bad one is not worth it and may lead to more problems. Once seated properly I have not seen a compression fitting go bad or leak. But I have seen old threaded fittings crack. Having said that in my house I have most kinds of fittings and once installed properly I have had no leaks. Of all the connections I had the most problems with threaded.

[Ian Gills]

Thanks tjbaudio, but threaded connections are brilliant.

They are so easy to install, virtually never leak when you put them on (if you use tape and dope) and are so easy to change out.

In contrast, I virtually always need to tighten my compression fittings a bit to stop them weeping when installing them and I find them hard to remove if they have been on there for years.

Threaded must be better. Possibly even better than soldered.

[tjbaudio]

I have threaded in my house in spots where that was the proper connection. I would never swap out a perfectly good connection of one type for another unless there was a reason to. Making a future shutoff valve replacement more easy is not a good reason, especially if it involves the same steps then as now.

[Ian Gills]

For someone with mild dyslexia that was a very well articulated response and with perfect spelling too. So well put, in fact, I must concede and will leave the fitting alone.

Thank you.

[tjbaudio]

Thank you. Some days the spell check wins, some days the Dyslexia wins. I have been told some of my misspellings are very funny. Especially after the spell check gets done finding exactly the wrong word.