# 18gr Platinum 950. How to melt!



## ALPHABiT (Jun 5, 2008)

Would like to make ingots of subject...
1200 °C fournace cannot work for sure.
Do you think i can attempt to melt in a little dish with my OXY-PROPANE torch???


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## Lou (Jun 5, 2008)

It'll melt fine with an oxypropane torch just make sure you wear some dark shades so that you do not burn your retinas from the intense bright light of 3200F/1700C platinum alloy.

Make sure you melt it in an alumina vessel.


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## ALPHABiT (Jun 8, 2008)

Sorry. Lou.
Tested.
It doesnt melt. Just near too, but doesnt.


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## Lou (Jun 8, 2008)

Oh yes it does melt. I just melted some Pt last night and Pd also. I used oxypropane too.

I'm not couch speculating my friend, I do this and it works. If it is not melting for you, I suggest you put all of that metal in as compact a crucible as possible. No flux required if you use alumina, the metal will not stick on it. Fused silica/quartz is really pushing it to melt platinum. 

It should take about 1 or 2 minutes to melt with an oxypropane torch with a good size flame. If you start from metal powder/sponge, I just put a little borax on the top of it and heat the crucible from the sides. The borax melts and keeps any of the powder from flying out so when I heat from the top powder just shrinks and shrinks and then heat-sinters into a pellet. Then you can really give it to it good.


Now iridium is a devil to melt!!!


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## Noxx (Jun 8, 2008)

Alfa, I think your cupel is absorbing too much heat. Especially if it's graphite. Try to use a different one, or try insulating it.

Just my two cent


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## ALPHABiT (Jun 9, 2008)

I use little Fused silica cupels to melt into, not graphite. I hate graphite, but have to use it to cast into.
How to insulate cupels? Uhm... Maybe i can make a "hole" to put into in the refractary stones where i work...
Ussually gold melt after 1 minute of large blu flame with oxy in that cuples.


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## Noxx (Jun 9, 2008)

You can insulate them with kaowool (also called insulating blanket lol)
Kaowool is a brand name but they are made from Zirconia Silicate I think.


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## Lou (Jun 9, 2008)

No kaowool is made from kaolin clay that has been spun into fibres, hence its name. It is an aluminosilicate and wouldn't be too good for this purpose as it will melt should the flame touch it.

Zirconia would be a good material to insulate your furnace with, except for the price!!

Alpha, my advice is that you give it more heat with a bigger torch!


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## ALPHABiT (Jun 9, 2008)

Lou, i'm using a bigger torch than the steve's video one...
In fact i melt gold faster then steve's video!
But i have to use it outdoor, so i think coating it's necessary.


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