Nightmare! Suspect sub standard solder.

[dennis more]

I've done a few sweated joints in my time, but probably not for 20 years (yes, I'm old), & have always used yorkshire fittings. Looking around the general opinion seemed to be end feed is the way to go, so I duly got the requisite bits, solder flux, solder, decent propane blowtorch & set to work.
I did some sections on the bench, where possible. Even then I was having terrible trouble trying to get the solder to run. Spent ages wire wooling the fittings & pipe, applied loads of flux but no joy. I realised I was applying too much heat to start with, but even on a gentle heat it wasn't much better - the solder just seemed to ball up & run round the pipe & on to the floor the second it melted. Eventually I had a bit of success, got some solder to run in the joints so, not very confidently, I tested them with water & they didn't leak (I know they should be pressure tested but I've always found, with yorkshires, they either leak straight away or don't ever). It's a gravity system so there's not much pressure involved.
I then sweated the whole system together
To cut a long story short I've had one tiny leak appear after several weeks, but 2 bigger ones appeared when I fired my stove up & the water got lukewarm.
I resoldered one, & that appears OK, but I decided to have more practice on the bench before doing the second. Again cleaned everything, flux, gentle heat so the solder just melted, same lack of capillary action. Removing the fitting showed the solder had only been drawn in on one side. By twisting, recleaning, refluxing & resoldering I eventually managed to get a complete coating on the end of the pipe when I pulled it apart.

I then tried plan B. I found a few inches of solder, left from when I used to touch up yorkshire joints I thought might have lost solder, & used that to make a fresh joint using another end feed fitting.

What a difference! Using exactly the same technique the solder ran straight round the joint & formed a perfect ring. 100% coverage when I pulled it apart.Hallelujah!

Confession time. The solder I recently bought was (marginally) the cheapest on eBay, but it is (allegedly) a leaded one, 3.25 mm, for plumbing, with a batch number.

Any ideas what sort of solder I've ended up with? Impossible question: should I take the whole shebang apart & start again?
That'll larn me.

Anyway, my thought for the day is: beware unknown solder!

 

[ShaunCorbs]

Never had a problem like that, normally down to fittings or pipe not clean etc what gas are you using ? Blue / red bottle or yellow

Also what flux you using ?

And solder I use this brand locally

Unleaded Plumbers Solder x 4 - Brand New!

And I would as your unsure / not 100% its sound

 

[dennis more]

Never had a problem like that, normally down to fittings or pipe not clean etc what gas are you using ? Blue / red bottle or yellow

Also what flux you using ?

And solder I use this brand locally

Unleaded Plumbers Solder x 4 - Brand New!

And I would as your unsure / not 100% its sound

Many thanks for that. Flux is borax, some obscure foreign make (Polish I think) but seems to behave just like my old stuff, gas bottle is a blue one.

I've taken apart & resoldered the offending joints using the few inches of old solder I had left. Again, totally different to the stuff I just bought - you could see it being pulled into the joint & ran round it in a nice even ring. I'm scrupulous when it comes to cleaning joints, & I did nothing different this time. The only difference I can see is the solder.

I'm just praying the rest of the joints hold! No leaks so far, but I haven't had the fire going yet. Fingers crossed.

 

[Ric2013]

I learnt to solder the hard way, out of a book and with a gas decorator's blowtorch, for a woodburning stove. When I first picked up a Superfire, my soldering was good almost immediately 🙂 . Which is what your experience reminds me of. In fact, I even had a slight leak which emerged after some time and I put silicone sealant over it. The hard water sealed the rest 🙂

I suspect the problem is too little heat (or misdirected) burning the flux before the pipe is hot enough to solder. Lead solder should melt at a lower temp than the lead-free in Yorkshire fittings. Lead not permitted now unless the water is not going to come out of a tap. Or, as you say, nasty solder.

Are you using flux liquid or paste?

Anyone else heard of borax being used as a flux?

 

[snowhead]

Anyone else heard of borax being used as a flux?

Looks like it's for Gold and Silver jewellery;
Jewellers Borax Cone used as flux for soldering gold & silver - TF241 | eBay

 

[dennis more]

Looks like it's for Gold and Silver jewellery;
Jewellers Borax Cone used as flux for soldering gold & silver - TF241 | eBay

Sorry, my wrong assumption, it's a rosin based RMA type paste flux. I seem to remember borax as being the usual alternative to corrosive types, but obviously not. It's my age or something.

I tried varying the temperature of the blowlamp from low to high, but no matter how gentle I was the solder balled up & fell off as soon as it started to melt. The old solder just ran in the joint as soon as it liquified.

 

[Ric2013]

I think you're more likely to burn the flux if the flame isn't hot enough.

I wonder what this weird solder is made from?

 

[AWheating]

Prob lead if it runs a lot better

 

[snowhead]

2 pcs Flux: rosin based; RMA; paste; metal can; 40g | eBay

Don't know whether to eat it or clean my teeth with it.😱

 

[Old Account]

Never heard abou pt borax and never seen it either in Poland. I don't think it's a polish product. Wouldn't trust this borax anyway. Definitely stick to my solder than this borax stuff though

 

[dennis more]

Never heard abou pt borax and never seen it either in Poland. I don't think it's a polish product. Wouldn't trust this borax anyway. Definitely stick to my solder than this borax stuff though

As I said, my mistake. It's a rosin based RMA type paste flux.

 

[Last Plumber]

You are letting the heat from the copper melt the solder?
not the flame!
Try touching the joint at the bottom so you can see it flood the joint and appear at the top

 

[bacon_sandwich]

Only time had trouble was when i tried to use some 15 year old flux, fresh flux and plumbers leadfree solder, heat fitting offer solder to the joint away from flame and solder flies into joint like a rat up a drainpipe.

 

[dennis more]

I heat the cleaned & fluxed joint until the flux starts to run, I then touch the solder to the joint (flame removed), heat a little more, try solder again, & repeat until the solder runs.
The suspect solder needs a great deal more heat to melt than my old solder; the flux really boils & smokes before the suspect solder melts & simply balls up. So I reckon the flux is being boiled off before the suspect solder melts whereas the old solder melts much quicker, the flux hasn't boiled off but is doing its job, & so the solder pulls into the joint in a nice neat ring.

I'm more than ever convinced I've got hold of some high melting point solder.

 

[Harvest Fields]

I was always taught not to put the solder anywhere near the pipework until the flux smoulders!