How to remove a soldered object?

[Niamh]

Hi everyone,
Sorry its me again!

I am making my dad a pair of spitfire cufflinks as a wedding present in rose gold. So far iv been practicing silver silver and im pretty pleased with how my planes turning out. Im using the delft clay method and its giving the plane such lovely detail i didnt think it would pick up for example the little bullseyes on the planes wings on the model are also being picked up and cast perfectly so im really happy.

My plan is to recycle old gold to make these cufflinks, I have bought a 1920's rose gold watch from a man on ebay (il have it tested when it arrives first to make sure its gold) but im fairly confident in him as iv bought from him before.

He said when he weighs the whole watch (with the thin leather strap and glass in the watch face) it weighs 16g so when the strap and glass is removed i should be left with about 9g of gold. Im hoping thats enough to cast 2 spitfires and allow for the spure?

Im also using recycled cufflinks, im melting down the cufflink blanks and removing the gold mechanism's off the backs and reusing them on my planes.

Only issue is these are soldered onto the current cufflinks they were made for, and they are yellow gold. How can i remove the backs from the cufflink blanks? is it as easy as soldering but im just taking off the part? and will yellow gold backs look really obvious next to rose gold? Thank you

[enigma]

I don't think 9g will be enough, you generally need 7-8g just for a sprue.
Yes, you can melt the solder connection to remove the cufflinks, or alternatively you could cut them off with a piercing saw and remove the possibility of melting any bits by mistake.
Yellow gold backs will look fine.

[Niamh]

I don't think 9g will be enough, you generally need 7-8g just for a sprue.
Yes, you can melt the solder connection to remove the cufflinks, or alternatively you could cut them off with a piercing saw and remove the possibility of melting any bits by mistake.
Yellow gold backs will look fine.

Thanks Enigma, I did question if that would be enough i guess it was wishful thinking! how much gold would you suggest to make 2 planes and accomodate the spure gold? thanks

[Dennis]

I shall confine my answer to the second question about removing the buttons for re-use.

You can't be completely sure that solder has been used, or what grade.
If you try to remove a large-ish flat decoration from a back plate it is too difficult without risking damage, so it is best to use the 'button' as it is.

To remove a stem or chain from the back, dangle it upside down with tweezers, flux and heat the join. Solder should melt and the button fall off.

To remove the stem or chain mechanically, I would cut off with cutters and then grind and sandpaper flat. You can also use a saw as advised by Sarah, but well clear of the back plate or you will have nasty saw marks to clean up.

As for colour, there is a mis-match between yellow and rose, but you can use the two tone as a feature if you like it. Dennis.

[Niamh]

I shall confine my answer to the second question about removing the buttons for re-use.

You can't be completely sure that solder has been used, or what grade.
If you try to remove a large-ish flat decoration from a back plate it is too difficult without risking damage, so it is best to use the 'button' as it is.

To remove a stem or chain from the back, dangle it upside down with tweezers, flux and heat the join. Solder should melt and the button fall off.

To remove the stem or chain mechanically, I would cut off with cutters and then grind and sandpaper flat. You can also use a saw as advised by Sarah, but well clear of the back plate or you will have nasty saw marks to clean up.

As for colour, there is a mis-match between yellow and rose, but you can use the two tone as a feature if you like it. Dennis.

Thanks Dennis, Iv bought a total of 16g of scrap gold from ebay sellers and things i had left round the house, all rose gold. Do you think 16g will be roughly enough to make 2 of these and allowing metal for the sprue? this casting in the photo is the same plane il be casting, but the finished one will have a tail! unfortunately thats the only part of this cast with silver that didnt work. Thanks

[Dennis]

Sorry, I don't do casting so I can't answer that part.
I also misread your question: if you want to re-use the cufflink findings, then cutting off close to the back with a saw is best. Dennis.

[enigma]

You need to weigh the silver planes and allow at least 7-8g on top for a sprue.
If its pouring ok with a small sprue in silver it should work ok in gold although the pouring temperature is hotter.

[handmadeblanks]

You need to weigh the silver planes and allow at least 7-8g on top for a sprue.
If its pouring ok with a small sprue in silver it should work ok in gold although the pouring temperature is hotter.

I believe the density of sterling silver is lower than gold so the planes will be heavier in gold even though they are the same size (Volume). If casting in 9ct gold they could be up to 20% heavier than sterling depending on the gold alloy.

[enigma]

Its around 10% heavier for 9ct so should be ok if she allows 7-8g for the sprue I would think.

[Niamh]

Its around 10% heavier for 9ct so should be ok if she allows 7-8g for the sprue I would think.

Thanks Enigma, Il give it a go and let you all know how it turns out! x