Soldering technique?

[macka09]

Hi all. Recently been having trouble burning the solder joints(black). I can't understand why, I haven't changed the torch or anything. It's really winding me up. Low flame high flame nothing helps???

 

[EPH]

What flux you using? Sometimes the flux on the outside of the fitting burns and then stains the pipe. Just be careful to keep the outside flux free and don't add any extra whilst your lamp is there.

 

[tolly]

Are you might be cooling the joint down too quickly?

 

[macka09]

Ha. Funny you say about cooking the pipe just recently a colleague has told me to use a wet rag to cool the joint and clean it. But his joints are fine. I use the flux in a black tub and red lid. Can't think of the name sorry lol

 

[Ermintrude]

Always add extra flux and Polish it with a damp cloth when done.

 

[leethegasman]

Soldering pipe up to 28mm. clean end of pipe going in to fitting,clean in side fitting,clean face of fitting (I use sand paper strip 25mm wide.add a little flux evenly to in side of fitting and out side of pipe insert and twist wipe off excess flux if any(most will say not to add flux to fitting as it pushes flux within the system)put heat on evenly warming fitting (move you flame around fitting) add solder to the opposite side of the fitting to where the flame is.(remember you won't the fitting to melt the solder not the flame )watch for the solder to run round gap in fitting (most important bit this means you have had a good joint using capillary action,remember its soldering not welding)I have seen so many installers over the years melting the solder on to the fitting then cleaning all the solder off with the flux brush.

 

[EPH]

Ha. Funny you say about cooking the pipe just recently a colleague has told me to use a wet rag to cool the joint and clean it. But his joints are fine. I use the flux in a black tub and red lid. Can't think of the name sorry lol

That's La Co, I find that the worst for tidy joints.

I use Everflux and the damp rag too.

 

[leethegasman]

Mistake using you flux brush on hot fittings because most fluxes are non active once you warm it so every time you wipe your joint with your flux brush the flux on it has been activated you then use the same brush to add flux to your next fitting.so adding crappy flux.

 

[leethegasman]

That's La Co, I find that the worst for tidy joints.

I use Everflux and the damp rag too.

Nice to see a good bit of soldering

 

[Paulplumb]

I don't think that's soldered yet. Tidy though. He must be on hourly pay

 

[macka09]

Always add extra flux and Polish it with a damp cloth when done.

Hmm. That's what I have been doing recently I never used to.

 

[Ermintrude]

Removes oxide, black layer and the dirt on solder. Then when set polish while hot with damp cloth

 

[Best]

Pull the torch away back from the fitting immediately the heat gets to exact temperature. Let the flux & the solder do the work - keep adding flux to the fitting by dipping the end of the solder wire into the flux. Try a different flux. I manage to still use the Frys Fluxite flux or similar Yorkshire Traditional flux, both grease based. Despite the higher temperatures needed for soldering lead free, I tend not to burn the flux & the solder flows brilliant with it & it is fairly harmless to copper.

 

[leethegasman]

Why the need to add more flux? If I won't to do a nice looking joint as APH has done in his picture I wipe off the excess flux that runs out when heated before adding solder so to prevent solder going every where.you only need to solder the joint not the outside of pipe and fitting.also dipping your hot solder activates the flux in your tub which buggers it up.perhaps that's why you have to add more flux because it's not very good due to keep putting hot solder in it.?
Just me or does this not make sence.

 

[village idiot]

I must admit I have seen many an ''Engineer'' adding more flux after soldering to assist in making a -so call clean joint, which is what erm is describing. But I have promised myself that it is a habit that I will never adapt to. I don't remotely approve of it. They like it but each time I see them do it, I shake my head in confusion.

 

[kris]

Neat bit of pipework there . The automatic bypass looks like a prv lol

 

[Ermintrude]

Neat bit of pipework there . The automatic bypass looks like a prv lol

Thought that too!!!

 

[village idiot]

I don't think that's soldered yet. Tidy though. He must be on hourly pay

Except he may have used one of those South African solder free method to glue the pipes together. Someone had that posted here recently

 

[billybob150811]

each to their own I use power flow which tends to grip and annoys people but it seems to have a lot of active flux and very little lubricant It doesn't run down the pipe giving the snotty look also use a turbo torch with mapp gas so over heat pipe but the joint seem okey and the soldering is good

 

[kay-jay]

For the neatest possible joints use a traditional flux. Cleane pipein a even ring around end of pipe and apply flux evenly as well. The solder wont run past the flux and you will be left with a neat ring of solder. Lots of people dont like traditional fluxes though. But you should at least try it and make up your own mind

 

[Best]

Why the need to add more flux? If I won't to do a nice looking joint as APH has done in his picture I wipe off the excess flux that runs out when heated before adding solder so to prevent solder going every where.you only need to solder the joint not the outside of pipe and fitting.also dipping your hot solder activates the flux in your tub which buggers it up.perhaps that's why you have to add more flux because it's not very good due to keep putting hot solder in it.?
Just me or does this not make sence.

The need to keep adding more flux is to keep the copper remaining thoroughly clean inside the fitting & on the edge of the fitting & the copper pipe as you are heating it. The flux just quickly disappears if you don't get all the correct parts soldered immediately. The area being heated will not turn black or tarnish at all while flux is occasionally added. I am normally only talking about a dot of flux at each side on fitting, if any extra at all. I want the outside joint of the fitting to remain clean as this lets me add solder & also shows how clean the joint is. The Traditional fluxes aren't affected by dipping the warm solder wire end in them.

 

[Kyle87]

Is it anything to do with the weather that you're now burning the fittings.

I used to use laco flux and last year I was soldering outside in the snow and I found that the flux was burning off before the plopped got hot enough to melt the solder.
I switched to the fernox fry stuff in the yellow tub which doesn't burn off so easy and my joints were perfect again even out in the snow.

I'm suggesting that as the op says it's only just started happening

 

[kris]

I've never used laco but it's something I do fancy trying , I think the black marks your describing is coming off from your pipe slices, do you regularly service them with some wd40 .?

 

[Kyle87]

I've never used laco but it's something I do fancy trying , I think the black marks your describing is coming off from your pipe slices, do you regularly service them with some wd40 .?

Laco is crap. Stay away lol

 

[kay-jay]

I use laco mainly.