Paging a real plumber

[F Murtz]

I am not missing a point maybe some Britishers may think that But silver solders to us is like the list given here.http://www.metalspraysupplies.com/mssa/images/silversolder.pdf

[Dave Plowman (News)]

Down to poor workmanship. Possibly also poor fittings.

[F Murtz]

[F Murtz]

It is much easier to soft solder than for instance silver solder copper to brass. Many an apprentice melts the brass fitting.

[F Murtz]

Ah so so silver solder is better because non poor workmen do it :)

[F Murtz]

All, in all new constructions

[Fredxxx]

This thread is throwing up a lot of confusion between silver soldering which is actually brazing (Hard Soldering), and silver solder, which is usually a eutectic of tin, silver and coper.

You would uses a copper silver phosphor alloy for brazing, and I have yet to see a plumber who would use it. You would need to see a red heat for any flow. Whoever specified it doesn't know what they are doing.

Soft solders that might be called "Silver solder" contain mainly tin and small portions of silver and copper to reduce the melting point to between 211 to 220. If you skimp on the silver, ie less that 3.5% melting point increases and passes through a "paste" stage when cooling that reduces strength.

[F Murtz]

The confusion seems to be what some British call a process versus the common use term in Australia

Yes whole countries, did you read the publication that someone posted?

Even to the extent that with annealed coil copper soft solder is prohibited and silver solder (copper silver phosphor alloy)compulsory.

[The Other Mike]

That is lead free for *electronics* purposes not plumbing, where it is tin / bismuth / copper with no silver in my experience

[The Other Mike]

Technically the term 'silver solder' commonly used in the UK is a brazing metal and the manufacturers refer to it as such.

[newshound]

So you don't know, then.

[Bob Minchin]

In order to get MCS* approval for my solar thermal system (approval to get the grant) all joints had to be threaded or compression fittings. Soldering is forbidden. I asked about silver solder as that was a much more compact method of getting from say 10mm copper to 1.5" bsp pump unions but they said "no". Plain daft as the header tank for the tubes on the roof is silver soldered and it is MCS approved in its own right as a system component.

*Microgeneration Certification Scheme

[Fredxxx]

I have now!

I see that brazing is required for medical gas pipes and for making branches, perhaps where I would use a preformed "T". And joints in concrete and for non-residential sprinkler systems.

I think annealed copper tube is more the exception as I can't see any issues with using soft solder anywhere else. It's not as if copper creeps, so perhaps it's an issue with the size of pipe. They don't seem to forbid compression fittings.

[F Murtz]

It is an exception you can use any soldering methods and various other methods for most copper here with some provisos on the fittings but the common practice now is silver brazing which we commonly call call silver soldering And it is specified on almost all new residential structures IE flats units industrial etc by the builders engineers and various others. in new single dwellings there is a lot of plastic but where copper is used, odds on it is silver soldered (brazed)

[F Murtz]

very strange,silver soldering(brazing) is miles better than compression.

[Andrew]

Agreed. And that is where our stupid Part P building reg came from.

Not where avionics is concerned. Lead-free solder is totally banned for anything important on a civil aeroplane. There are plenty of photos of how lead-free joints fail on the web. There is one taken by cutting open a transister can showing the 'whiskers' that seem to develop.

And anyway, I thought the refridgeration industry always brazes copper pipework, and the pipe ends are usually flared on site using a special tool whose name I forget.

Domestic copper piping has always used preformed sockets that are (were) more suitable to low(er) temperature lead-based solder that uses capillary action to fill the joint.

everything is different in Oz. I believe soldering electrical mains cable is the preferred method, while we use junction boxes or crimps.

[F Murtz]

Dont know why I bother as I do not need to have it on the tip of my tongue as I have been soft soldering silver soldering (brazing) gold soldering for over 60 years without bothering to look it up

Soft solder is typically thought of when solder or soldering is mentioned, with a typical melting range of 90 to 450 °C (190 to 840 °F).[3] It is commonly used in electronics, plumbing, and assembly of sheet metal parts. Manual soldering uses a soldering iron or soldering gun. Alloys that melt between 180 and 190 °C (360 and 370 °F) are the most commonly used.

[F Murtz]

No, use lots of methods. but you we us do have a lot of differences in general house work (ring mains etc)

[Robin]

Thanks. That ties in precisely with what I remember my late cousin (a ten pound Pom) telling me.

[Andrew]

Why ?. Most houses built in the 60's and 70's (like mine) have solid floors. On top of the construction slab the 3/4 inch screwed iron gas line for the baxi bermuda back boiler and kitchen was laid, and also the

15 and 22 mm copper central heating runs. These were 'soft' lead soldered (using cheaper gas and equipment), wrapped with felt stuff, and then the 80 mm of screed laid over the top. Provided the copper is isolated from anything cementitious or gypsum based, it is remarkably self-protecting. High temperature brazing of copper (which I believe requires a special grade of copper pipe = more expensive) is only used in the refridgeration industry. Horses for courses. And these days it is all dumbed down and replaced by push-fit barrier plastic.

Unless you were unlucky to have poor quality copper pipe which pin-holed (common during the 70's copper boom) this will last the life of the building - typically 80 years. My house is 38 years old. The lead-soldered copper pipework is in perfect condition.

The important thing was to clean off the acidic flux which many lazy 'Can't get me I'm in the union' types didn't bother. Same goes for flushing before adding inhibitor.

Are australian houses (other than in Melbourne and Hobart) built with central heating ?. Why would you need it in Brisbane or Cairns ?.