solder ring woes

[rookie]

When I attempt to execute a join with a solder ring fitting I'm finding that I generally get small gaps in the solder ring when it soldifies. However, whilst the solder is liquid I do achieve a solid ring, some of which seems to be sucked back inside the joint on cooling to form the gaps. I've dissasembled numerous samples of my countless "failed" test joints (I though soldered fittings were supposed to work out cheeper ;) ) and both the pipe and the fitting are nicely coated in solder. From information I've got from previous postings to this group I understand I should be able to consistently achieve a solid ring of solder, otherwise my joint is suspect. Is this corrent ? If so, I've followed all the advice I could find from previous posts about solder ring joints. i.e.

- cut pipe ends square with a pipe cutter

- clean the pipe and fitting until shiny with wire wool

- apply flux to both

- heat the joint evenly with a powerful torch until you can see a ring of solder

- don't move the joint for a bit ... and was wondering if anyone could suggest what I'm doing wrong?

Thanks

-Neil

[Stuart]

I've done loads of solder joints and never had this problem . Are you dislodging the solder when maybe cleaning it a bit too vigorously .???

You could try adding some solder to the joint as the solder melts ..

Stuart

[Andy Cap]

Clean both the pipe and inside of the fitting. Be sparing with the flux and it WILL work.

Andy

[fred]

[Chris Bacon]

Your technique seems fine... are you *sure* you've really got a problem? I wouldn't expect, with a solder ring fitting, to always get much of a ring outside the joint after it's cooled. That you get a continuous coating inside the joint is good. You could try adding extra solder, as mentioned by others, but be careful that you don't add so much that it drips off inside the pipe, which can cause problems such as little balls of solder tinkling away in the pipe when there's a flow of water through it, or long streaks of solder in the pipe like straws cut lengthways.

[Dave Plowman (News)]

Not having a perfect ring of solder showing at the edge of the fitting after cooling doesn't matter. You've established that on dismantling you've achieved perfect tinning of both surfaces.

What matters is that you've seen the solder flow all round the fitting before setting.

BTW it's even cheaper to use end feed fittings.;-)

[daddyfreddy]

If you mean you're not getting a solid ring inside the joint then , yes, that is suspect. Outside it doesn't matter. After applying flux always twist the fitting or pipe to ensure the flux is smeared all the way round. You also may be applying too little flux. While you're experimenting, you might want to try using end feed fittings and add your own solder.

[Holly, in France]

End fittings might be easier and definitely cheaper. You can keep putting them together and taking them apart to see how you are doing. One other thought though. We had a problem with the usual end fittings when we switched to lead free solder, it wasn't tinning properly. Tried a few joints with solder ring fittings, no improvement. Turned out to be some sort of incompatability with an old tub of flux. I imagine the contents of solder and fluxes are the same in the UK as in France, so it might be worth checking. Bit of a long shot though.....

-- Holly, in France Gite to let in Dordogne, now with pool.

[Aidan]

You should ream the pipe out afterwards so that there's no restriction to the bore; won't affect soldering though.

Don't use wire wool, it leaves strands of steel wire all over. Use this stuff, pipe cleaning abrasive strips;

must be clean. Active/acidic flux reduces the need for cleaning, but it's nasty stuff. You ned to ensure you flush it out of heating systems and use it sparingly.

In theory you should apply flux sparingly to the pipe only, so that you won't shove a lump of flux up the fitting when you assemble it. Twist pipe in fitting, to distribute the flux evenly. Take a few fittings apart before soldering to ensure you're getting get a thin, even coating of flux on both parts. Cleanliness and a thin coat of flux is the key.

Practise. Get someone to show you.

[Aidan]

And it's coated with oil or something to stop it rusting; the worst thing you can have in a soldered joint.

[Dave Plowman (News)]

car after body repairs. It's also excellent stuff for cleaning burnt on grease etc from stainless steel grills in an oven.

[Holly, in France]

What colour is it? I'm wondering if it's the same sort of stuff that we use. Ours comes on a roll though, dark reddish brown.

Different topic, train of thought....in the picture on the site it looks like a sort of mesh, I don't suppose it is. We got some mesh sanding product recently which was supposed to be better and clog less for sanding down taping and jointing. It didn't seem much good, we are back to the sanding sheets. Anyone else had any success with the mesh stuff??

-- Holly, in France Gite to let in Dordogne, now with pool.

[Dave Plowman (News)]

Ah - it was mesh stuff I meant. But dark reddish brown.;-)

[Holly, in France]

Well, maybe the plumbing stuff *is* mesh ?! Aidan?? Then again what you found could have been the stuff for plaster, although......

Nope, the plaster stuff is black! I s'pose the stuff in your car was probably another super duper product specially for car body filler! At least with sanding products you can see the need for all the different ones, not like those blasted ceramic tap bits :-)

-- Holly, in France Gite to let in Dordogne, now with pool.

[Matt]

[Aidan]

It is a mesh, I don't think it's woven, but it's got about 1.5mm squares going through it. Good for cleaning tube ends, no good for taking swarf off, so limited abrasive qualities I think. Haven't used it for anything but tubes.

[Rob Morley]

Is at least one of the pipes that you're joining open to the atmosphere at the other end? If not it could be that the air inside is contracting when you take the heat off, and sucking the solder back before it solidifies. I've never seen this in plumbing, but it can be a problem when brazing things like bike frames.

[rig doc]

Hi Rookie,

Most shops seem to be selling lead free solder, and while it's ok... I find leaded solder much better and provides a better quality joint. When soldering, I recommend the use of wire wool to clean the end of the copper pipe and if possible the inside of the joint. Old dirty joints can cause soldering problems. Are you using new joints? Allowing the joint to move while cooling can cause fracturing of the solder joint. Often while the joint doesn't look good to the eye around the rim of the solder joint, it's actually fine inside where you can't see. After fluxing, heating and soldering, while still hot, twisting the joint round on the pipe can spread everything about a bit and help to make a better joint with poor joints.

Cheers

[mike]

Rob Morley wrote in news: [e-mail]:

I have :-(

It's easier than you think with stopcocks and taps out of sight and out of mind.

I was going to mention it, but you got there first

mike

[Dave]

That sounds like Scotch Bright. Does it come on a roll that can be up to

200 mm diam or more? Is it about 100 mm wide?

Dave