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Novice copper pipe soldering

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disco_monkey79

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Hi

I have been undertaking small plumbing tasks using compression joints. However, for some bigger tasks that I'd like to do (moving most of the radiators), it's going to get expensive.

Has anyone self-taught themselves copper soldering? And how do you know (other than refilling the pipes with water) that you have got a good joint? Is it fairly obvious from looking (i.e. a clear bead of solder all round)?

I would obviously practice on scraps before attacking the CH system, but can only perform rudimentary tests...

Thanks
 

PaulR

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Yes, following YouTube tutorials and practicing as you say. Alternatively for hidden pipework pushfit is your friend


Sent from my iPhone using Tapatalk Pro
 

Bm101

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Buy a torch. Rothenburger etc. A heat resistant mat. Solder, flux, some cheap small brushes and some wet and dry. You can buy a small internal burring brush. Then buy a bag of joints some pipe from a merchant's. Not a diy shed as you will pay through the nose.
By the fifth try you will have the heat transfer rate about sorted and produce reliable joints. Testing the system is your fear to face! :D

Its definitely possible if you are handy.
You know a good joint once you've made a good few practice ones. A clear bead of solder is a good sign. A pro will produce invisible joints but as long as you are tidy and not over/under cooking every joint you'll be fine . I replumbed my kitchen in copper first time. No issues.
 

Rorschach

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Yorkshire (solder ring fittings) are good for starting out as you can learn about fluxing and getting the heat right without worrying about how much solder you are putting into the joint.

A length of pipe only costs a few quid and the same for a bag of joints. Do plenty of practice and you will soon get the hang of it.

I learned from youtube videos followed by practice, my joints are not exactly the prettiest but they are strong and don't leak.
 

Lons

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Just a couple of points,

* Clean, clean and clean again and that includes the inside of new joints as well as the pipe.
* Don't overheat it, once the solder flows take the heat off, if end feed joints add solder if pre-soldered the damn stuff will all flow out if overheated so you may as well have bought end feed.
* Don''t move the joint for a few seconds until the solder has hardened or you can weaken the joint and won't know until it leaks.

+1 for a Rothenburger torch though they're not cheap.
 

AndyT

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One thing I learned when moving a radiator in a friend's flat is that you can't get enough heat on a soldered fitting with a diy torch if the pipe you are connecting to is full of cold water. :oops:
 

TFrench

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Rothenberger auto ignition torch and mapp gas is awesome. Plus handy to have around for warming up stuck bolts! My first go at soldering was a complete utility room - hot and cold water and a radiator. Seriously nerve wracking, when I turned it all on. No leaks though. Keep it clean, polish everything with wire wool, flux it, use yorkshire pre soldered fittings till you have the hang of it. Simples.
 

jimmy_s

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Its not difficult. You are relying on capilliary action to make a decent joint so firstly ensure that the surfaces are clean, give them a rub over with a bit of fine wet and dry if in doubt then flux joint and assemble. If you are soldering a tee or elbow and are using solder ring fittings, assemble the whole lot before applying heat and apply heat to the pipework adjacent to the fittings and allow the solder to flow. Let it cool before cleaning the flux off. You dont need that much flux. If using end feed you apply the solder to the pipe just before the junction and will see it flow into the joint.

If you have water lying in a section of pipe you are best just using a compression fitting as you will find its virtully impossible to solder as the water just draws the heat. Even if you get the solder to flow chances are you will end up with a leaky joint with steam leaking out as joint solidifies.

Get a few fittings and have a go - its not that difficult.

Rothenburger torches are the best but not cheap. Mapp gas is certainally useful for larger bore such as 54mm but for most domestic stuff normal propane is fine.

If you are soldering potable water and are using end feed remember to use lead free solder.
 

sunnybob

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Just to expand what Jimmy says, for someone who has never soldered.
Clean inside and out thoroughly, use flux immediately inside the joint and outside on the pipe.

The solder moves to the heat. it will actually climb to the heat. Its called capillary action and that fact is your best friend.

For example, if you have an elbow to solder and one pipe is rising vertical, heat the lower pipe and elbow first, just away from the elbow. Keep the heat moving around the pipe and although moving across the elbow often, concentrate on the pipe about an inch away from the joint. Assuming you are using yorkshire fittings (not cheap, but by far the easiest to learn with), you will suddenly see the solder ring appear. That joint is done. Move the heat to the upper pipe just above the joint with an occasional swipe across the fitting. Remember, that fitting is still very hot from the other joint. As soon as the solder ring appears, youre done. Wipe immediately with a wet cloth to remove all the flux.

If you dont move the heat around the pipe the rear of the joint will not be solid. If you keep the heat in the joint the solder will run down into the elbow and either not seal the joint or partially block the elbow causing flow problems.
If the solder ring appears in one spot only, you can make it move around by leading it with the heat.
 

Gerry

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If you have a joint with water in it it will be impossible to get it up to heat.
If this happens simply pack some white bread in to the pipe to act as a plug. Once you turn the supply back on it will disolve and be flushed out.

Gerry
 

Rorschach

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You might have already considered this and discounted it but in case you didn't know there is nothing wrong with using plastic pipe and push fit connectors for radiators.
 

Marineboy

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I now use plastic pipe and push fit, just installed a bath in my extended bathroom, it is brilliant stuff and very forgiving for an amateur despite some of the scare stories about such fittings failing. I also had to move a radiator as part of the new bathroom layout and used plastic for the underfloor run but in my view would not look good exposed so used copper to go from underfloor into the rad itself.
 

Eric The Viking

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1: Start off with LEAD solder, not lead-free. It has a lower melting point and is more ductile. Toolstation et al sell it for plumbing. It is not suitable for potable water, although there must be many millions of joints made all over the planet using it.

1a: Don't even think about butane (from the DIY sheds). Use propane, or if bold MAPP gas (hotter), with a decent torch head - Rothenberger are excellent, so are Primus Sievert (although recently not popular). Both the latter gases will boil off any water drips in pipes you cannot fully dry beforehand, but butane will not, meaning your joint stubbornly stays at 100 C, and the solder doesn't melt properly, and you get a failing joint or none at all.

2: I recommend LaCo brand flux. I've used it for four decades. You don't need much more than a smear on both surfaces (and dip about 3/4" of the solder wire before applying it to the joint. It does sting on the fingers though - I keep a jam jar of water and a roll paper towel handy, as it's just too convenient to use a pinkie to get flux into the fittings. Yes, I know of "flux brushes" too!

3. If you can, clean with wire wool. There are stiff wire brushes, and even perforated emery cloths available, and branded as pipe cleaning tools: they work, but unless the pipe and fittings are really badly oxidised or corroded, they are unnecessary and leave nasty scratches - you want reasonable smoothness for good capilliary action, taking the solder right into the joint.

4. Get a pipe cutter. This saves time, and makes a far neater cut than any hacksaw, Dremel tool, Goldfinger laser or whatever. I like the "Pipeslice" type, but the traditional ones that advance the cutting disc with a screwthread (adjusted by hand) work just as well. keep it clean and slightly lubricated - the flux will deal with tiny traces of oil, but the device will cut better. They are more awkward and won't work in confined spaces (Pipeslices will), but one size will do several sizes of pipe.
Pipeslice type:

Traditional type:

I have and use both styles above. The lower one uses the "tighten a little, twist a bit, repeat" method.

The fold-out "spike" in the side is to de-burr the ends of the pipe after the cut. Pipeslices usually leave a neater cut for some reason, so I rarely bother when using them, unless non-turbulent flow is really important. If you do attempt cutting with a hacksaw, your fingers only have you to blame, and you will probably need a fairly fine cut rat's tail file to clean up afterwards. The good news is that fittings don't really need a perfectly square end to the pipe, but don't be silly about it, and you must remove all swarf from inside the pipe, or expect valves and taps, etc. to leak or fail.

5. Learn on end-feed fittings - the ones with NO solder pre-fitted into them. This is for several reasons: (a.) you'll get more confidence - it's a lot easier than it looks, (b.) they are cheaper than any other sort of joint, (c) you can even do one end of the fitting and the second (or third) connection separately. You will also get a feel for how much solder you need to apply.

6. Heat the pipe(s) first and mostly, NOT the fitting. Heat is transferred to the fitting very well by copper, but if you heat the fitting you will likely overheat it and burn away the flux, giving a "dry" joint, i.e. a potential failure. Just play the flame over the fitting for a couple of seconds occasionally while you mostly heat the pipe(s), say a 1:4 ratio in time or even smaller than that.

7. Turn your blowlamp down fairly low, at least to start with. With a Rothenberger head running propane, I struggle to get it as cool as I'd like (yet still keep it lit). Low heat gives you time to get everything just so. You will see the flux clean the pipe and fizz a bit, after that happens count to 5 slowly, take the blowlamp away for a sec, then wipe the end of the solder around the end of the fitting to see if it leaves a silver trail behind - if so, you are nearly there - little more heat and solder together will make the joint. Wipe the solder roughly 2/3 - 3/4 round the pipe. gravity and capilliary action will close up the solder ring.

8. You almost certainly need much less solder than you think you do (beginner's mistake), but you do need heat - once the solder liquefies and flows, keep heating for a few seconds longer. It's partly to ensure any flux residue clears from the joint, leaving only solder all round. The solder won't all fall to the bottom side under gravity - don't worry about horizontal joints, and when doing the underside of vertical ones, relax - the solder will flow up to where it needs to be.

8a. Why does flux residue matter? If you use a lot of flux and solder, but insufficient heat, you can make joints that fail. It's rare but you get an incomplete ring of solder, with a narrow plug of burned flux filling the gap. Flux is intended to be water soluble, so it can be cleaned from the inside of the pipework. So you make your joints and check them and they are fine. two days after you fill the system with water you have a pinhole leak! But don't be fooled: "pinhole" is a comic term used to make the plumber really embarrassed as they stand there with mop and bucket - it will leak a LOT of water under pressure!

8b: Buy an inspection mirror, and use a small torch (I mostly use a bike LED headlight). Wipe the finished joint clean with a damp cloth then have a good look. As long as you are sure you can see a complete ring of solder, it's probably fine. Rectangular inspection mirrors are probably more useful than round ones, incidentally - I often get frustrated as I can't quite see the bit of the joint I need to. But relax - if you experiment by doing just one end of a straight capilliary coupler you will easily see how well the solder "wicks" right down to the end of the pipe in the fitting - it's a lot more robust than you may think initially.

9: Neat plumbing starts with neat pencil lines on the wall marking the centrelines of the pipes, followed by pipe clips. Dry-fit stuff together before doing anything else, to ensure you don't wrongly measure something then embarrass yourself. DAMHIKT!

10: one of the best things about end-feed fittings (apart from neatness) is the ability to pre-assemble sections of pipework. I use an old school-chemistry retort stand and clamps to hold stuff together at the easiest angle for soldering, and make the joints out in the back yard (anywhere convenient). home-made wooden clamps would do just as well (15mm and 22mm are outside diameters, for the purpose of clamp making). This also lets you wash off, wash out, and generally clean the assembled section before you fit it. As I said, you can solder any two ends of a Tee-piece, thus ensuring those joints are good, before doing the third end. It takes a little practice, but heating mostly the pipe and rarely the fitting gets it done well and neatly.

11: the time will come when you have to solder a pipe that has to be clipped in place first. Copper conducts heat really well, and you can melt pipe clips if incautious. I try to avoid joints closer than around 3" from clips, but in the extreme, GENTLY clamp a mole wrench between fitting and clip, next to the clip, to act as a heatsink. Works a treat.

12: This is the next step: pipe bending lets you do stuff for which no fittings are available, and gives quieter pipework as bends are radiused. It's neat if it's done carefully. You have a choice of springs or pipe benders for 15 and 22mm. Both stop the tube collapsing. Springs go inside the pipe, benders fit onto it. Sizes smaller than 15mm have springs that go over the pipe. When using springs, bend slightly more than the angle you need, then back to the correct bend. This frees the spring from the pipe (otherwise good luck with getting it out/off!). I prefer a pipe bender for 15 & 22mm, and external springs for smaller pipe sizes (small benders are usually rubbish in my experience). As supplied, fresh tube is slightly work-hardened. Copper anneals very easily though, so heat the length you intend to bend with your blowlamp and let it cool, then you'll find the bend is far easier, and probably neater. Don't go nuts, for 15mm, the tightest bend you can reasonably make is probably about 60-80mm radius. Too tight risks the pipe wrinkling or collapsing (good luck recovering the spring at that point!). It's not an issue with a pipe bender, but they do need lubrication and to be kept clean to avoid wrinkles on the inside of the bend. Also protect the straight former that comes with the tool - damage to the edges of it also causes wrinkles.

13: when we went metric way back in the 1970s, 15mm replaced 1/2" pipe and 22mm replaced 3/4". But the way of measuring changed, too: 1/2" is the ]inside diameter of the pipe, 15mm is the outside diameter. Same with 3/4" and 22mm, but 22mm is significantly bigger and the difference is obvious. With 15mm and 1/2" it is VERY, annoyingly, close (1/2" OD is 15.88mm I think). Using compression fittings ("Conex", "olives", "spannered", whatever), you can just about fit either sort of pipe in (if the olives compress properly), but you cannot do this with soldered joints - they can sometimes be forced together, but 15mm is too loose in an old fitting and 1/2" too tight in a modern one. The solution is to use emery cloth to reduce the outside diameter of 1/2" pipe until it fits. It takes a while!

Why mention this at all? Recently, I was surprised to find a length of 1/2" pipe had been used in our solar heating installation, installed in the late 1990s. I think the plumber, working in our attic, had found a gash length of 1/2" pipe I was keeping (for a very rainy day), and used it. All the joints were compression fittings, so it didn't matter back then. I expect 1/2" in old properties, but I thought I'd long ago removed the last of it in this house, and never expected it in a recent installation! If in doubt measure, it rather than getting stuck in with the flux etc. only to find it won't fit!

Way too much info as usual. But some might be helpful...

E.

PS: I am old-fashioned. I won't have plastic pipework in the house, other than for waste pipes. That may mark me out as a Luddite, but I have seen quite a few leaks (elsewhere) when it hasn't been done properly. Your mileage, etc.
 

Marineboy

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Eric, that is an excellent guide for plumbing in copper. I must say there is nothing more attractive than a neat copper installation. For me though, plastic is the way to go. Perhaps when it first appeared it may not have been totally reliable but I have spoken to several plumbers/heating engineers who swear by it. Once you put on the fitting it is literally impossible to pull it off so mains water pressure won’t either.
 

Rorschach

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Marineboy":28tt3yd3 said:
Eric, that is an excellent guide for plumbing in copper. I must say there is nothing more attractive than a neat copper installation. For me though, plastic is the way to go. Perhaps when it first appeared it may not have been totally reliable but I have spoken to several plumbers/heating engineers who swear by it. Once you put on the fitting it is literally impossible to pull it off so mains water pressure won’t either.
I agree, nothing wrong with plastic pipe and fittings. Pushfit and copper pipe also works well and I use that combo quite a bit as well.
I still solder of course, though I almost never use a compression fitting these days, anything that I would have used compression on I now just use pushfit.

Really it's all about what is best for the job at hand, the access you have now and the access you might have in the future.
 

gregmcateer

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Totally agree with Lons.
Did he mention CLEAN?
Also, when heating a joint, move up and down from past one side and over the joint, to past other side, so heat is quite even- this causes the solder to run.
And leave it to cool before moving it, (or touching it! DAMHIK
A few practice goes and you'll get a feel for it.
And clean off the flux afterwards, otherwise it'll all go green and horrible.

Lons":270luo2x said:
Just a couple of points,

* Clean, clean and clean again and that includes the inside of new joints as well as the pipe.
* Don't overheat it, once the solder flows take the heat off, if end feed joints add solder if pre-soldered the damn stuff will all flow out if overheated so you may as well have bought end feed.
* Don''t move the joint for a few seconds until the solder has hardened or you can weaken the joint and won't know until it leaks.

+1 for a Rothenburger torch though they're not cheap.
 

Phil Pascoe

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Whether using copper or plastic, a good plan is to minimise the use of connections in places that will become inaccessible. Plastic has the advantage here as you can use much longer lengths.
 

Eric The Viking

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I have a close friend who has been Clerk of Works for two housing associations, focused on their new-build projects, some involving 100+ dwellings. He is not a fan of plastic, and the HAs insist that if used, all joints must be accessible (so for example, you are not allowed any under the floor). We had a small amount of 22mm used temporarily whilst reconfiguring the system. I was rather surprised to find that the fittings for it went alarmingly yellow (even in the dark), and showed signs of surface depolymerization. That was on mains-pressure cold water 22mm, and it scared me. I also sadly saw a friend do an impression of the Trevi fountain under their bathroom floor. I don't know what had been done wrong, but almost none of the joints actually didn't leak (and there were many joints!). Thankfully it was a test with the floorboards still up, but it made rather a mess, within seconds, and it reminded me why the housing associations insist that joints are not hidden.

Obviously it wasn't done correctly, but I'd still rather stick with something that for me is neat and straightforward, if a bit slower. The other issue is finding pipes at a later date in stud walls. I can just use a metal detector, but with plastic, you have to hope the plumber didn't do anything stupid, such as running a pipe on a diagonal. There may be pipe detectors that work reliably with plastic pipes* but I have yet to see one for small trade/consumer use.

Then there is the question of electrical earth bonding/continuity, etc. It's a debated issue, and I don't want to dig in here, but it can be a nuisance.

E.

*I know there are such in the commercial world - I have a friend who sells them to water companies - but they are complex and usually, I think, need a transmitter located in the water system somewhere (the pipe detector picks up its signal).
 

Woody2Shoes

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+1 for all of Eric's wisdom. If I had 10p for every tale of woe I've heard relating to plastic plumbing, I'd be able to buy myself a pint or two!
 

disco_monkey79

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Wow, thanks for all of that - it's reassuring to hear that plenty have self-taught, and the 12-point reply was brilliantly informative.

I have solid walls and concrete floors, hence enquiring about copper, as it will be on display, eeeek.

Thanks again, I am going to have a play.
 
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