Scrapyard Copper and silver solder

[AdelaideJon]

Hi All,
I have recently found some 2" copper pipe at a reclamation yard. They sold it to me for scrap price; so $25 for 1.9 meters.
It is quite dirty and has some copper oxide on the inside of the pipe. I started to clean it with vinegar and nylon scourers but it is still not 'like new'.

I was just wondering if this is safe to use? They are generally used for water pipes but ultimately no one will ever be able to tell you where this scrapyard copper came from. could lead from other pipes/solder have leached in?

The rest of my build materials were quite expensive so i don't want to ruin it with crappy copper. But also, if its safe, its safe.

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Also I when to BOC today to try and get some nice ProSilver15, which was recommended by someone on this forum (thank you). But the guys there said that it was not food safe?
The alternative they offered was called ProSilverT56 i think and it was $500!!!!!! Thoughts?

thanks

Jon

[Yummyrum]

Welcome jon .

My first 2" copper score was similar to yours . Sorry but vinegar won't cut it . I frigged around with that and citric acid . Finally found that sulfuric acid will clean the stuff up . You an get a 1 liter bottle of 98% concentrated sulfuric. Acid from most chemical supply places for about $10 . Add it to 20 liters if water and you have the best copper cleaning product in town . It will clean that manky second hand stuff you have to pinky copper goodness in about 1/2 an hour .
I found if you get a length of 90mm pvc pipe a bit longer than the 2" and cap one end you can stick your pipe in it and fill it up

Re the solder . Are you wanting to soft solder with lead free solder or braze with silver brazing rods ? Those rods you are referring to sound like brazing rods . Do you have an oxy acetylene torch because you will need one . Even Mapp gas will be figting a loosing battle to get 2" copper up to brazing temp . Most folk us soft lead free solder which can be used with a butane or mapp gas torch

[AdelaideJon]

Thanks Yummyrum, that's a good tip. I will definitely be doing that!

It was indeed brazing rods i was talking about. I thought it would be a little stronger. These fittings seem to have a reasonable tight fit though so i guess i just need a vapour sealant like solder. I was going to be using mapp gas so that is another piece a good info about the temp issue. Thanks!

I understand that some solders can also have cadmium in them to replace the lead. I would rather buy some solder where i know all the ingredients, but this seems to be hard to come by...

[Kareltje]

Be very carefull with strong sulfuric acid!!!!!!
Always poor the acid quietly in the water, never ever water in the acid!! for example! When the acid dissolves, a lot of heat is released and you could cause an explosion, like when you throw one drop of water in an oil fire!

[cob]

here in the states we can buy a product called ZAP it is a basin tub and tile cleaner in a spray bottle

available in most grocery and hardware stores, it contains sulfuric and muratic acid, and cleans copper well.

CLR also cleans copper well and quickly. if these brands are not common down under look at the labels

of cleaning products that claim to clean tile, calcium, lime, and rust.

rubber gloves, eye protection, and good ventilation is highly recommended.

[Yummyrum]

Jon , lead free soft solder is perfectly adiquate . Unless you are doing a butt joint .
Bunnings have Aquasafe lead free solder which is what all us Aussies seem to use with Bakers flux . Don't use Berzomatic flux paste .....it sucks big time .

Look you can use Mapp on 2" to Braze if you still go that way but anything longer than about 200mm long will start to dissipate heat as quick as you are putting it into it .IE you will use a can of gas to get it barely hot enough to braze .
The solution is to stick the work piece on a one or two ring gas burner for about 5 minuates to pre heat it then you can bring it up to red hot brazing temp to do the job

[AdelaideJon]

Thanks Yummyrum,

https://www.pscoop.com.au/uploads/safet ... df?t=30020" onclick="window.open(this.href);return false;" rel="nofollow

I think we have a winner. 99% copper and 1% tin. Nothing bad in that. Thank you.

Sulphuric seems to be quite expensive and hard to come by. Hydrochloric acid is easier to get, but i think Kareltje Is right in saying it is very dangerous and maybe not worth the bother. I can get CLR in AUS so i will look at that. Thanks Cob. Bunnings will surely have something to clean it up!