Soldering Copper

[Nick martin]

Am I right in assuming that you can simply use silver solder on copper pieces?

If this is the case, then how do you prevent the copper from becoming discoloured by the silver, or indeed how do you correct it when polishing? Or do you simply leave it once done?

I dont have any copper jewellery at hand so apologies for sounding so clueless!

Nick

[mizgeorge]

Ah, and therein lies the secret. The trick is to use just the right amount of solder to make the join, without having enough excess to flow over the rest of the piece. And that's not always easy! If you do find you've been a bit overexuberant with the solder, it's just down to a bit of work with an appropriately shaped file. I find the coarser grades of radial disc do the job well too.

Copper can be tricky to solder, it takes a lot more work to keep the piece hot enough to make the solder flow - I tend to end up using two torches, but I'm sure others have better solutions.

[Dennis]

Sadly, although there is some copper solder around it is not copper coloured, but in some situations splashes of silver can be quite decorative. To hide the silver as George has said, the join must be quite neat and the solder placed at the back where any surplus won't show.

For sweat soldering you can make a small bevel on the lower edge of the top sheet, which helps to keep the solder back.

Disguising the silver can be achieved by electrolytic plating:
Either by temporarily dropping an iron nail into your pickle along with your finished piece, or using a battery, a copper electrode and salt and vinegar solution. (see my thread 'Salt And Vinegar Anyone?').

Dennis.

[Nick martin]

Many thanks to both of you, thats a very comprehensive answer thank you. I'll check out your thread later on this evening Dennis.

Cheers,

Nick

[Nick martin]

So... I've made my first hollow bead via my new disc cutting / doming set and have to say Im rather pleased with myself as tragic as that may sound!

Getting back to disguising the silver solder Dennis, does dropping a nail into the pickle only work with certain types? I use the picklean powder from Cooksons and tried a nail with the bead in the same solution this evening and it didnt have any effect, so any ideas on this please?

Ive attached a photo so you can see where Im coming from.

Cheers,

Nick

[Dennis]

Yes Nick, the electrolytic effect is quite thin and self limiting. Do this with a scrap of silver and you will see the pink copper coating.

That is why I tried the method using the batteries and a copper electrode in salt and vinegar solution, which was a bit better.

However here is a knack to having thin seams on balls: Rub the edges of the domes on flat abrasive paper so that the halves match up. Place solder pallions on the inside of each, near the edges and warm so that the flux dries and holds them. Then wire the halves together and heat. The solder will run without much showing, provided you stop heating as soon as you see it appear.

You probably know that its best not to re-heat closed soldered objects before making a venting hole, incase they explode.

[mizgeorge]

I *think* picklean may be one of the 'steel-safe' non-acid pickles, in which case it may not work in the same way as conventional pickle. I know there's no reaction with Black Magic or whatever it's called.

[Nick martin]

Thanks for that. The technique of soldering the domes from the inside sounds like the way forward without a shadow of a doubt!

I couldn't figure out how to achieve this ( ie holding the solder in place ) but you've just answered it perfectly in your reply. Back to the drawing board and thanks for the tip.

Nick

[Nick martin]

Worked beautifully this afternoon and the visible thin line of silver solder is barely visible. Ill utilise this method for many projects from now on as its so clean. Top tip.

Nick

[Dennis]

Good for you, Nick. Dennis.