Smelting Platinum

[Jim Morrison]

I've searched the site looking for the answer before posting this, if I missed a thread with the answer to my question please forgive me. Can someone who is smelting platinum please offer guidance for an oxy-hydrogen torch setup? I went into the Airgas store and they recommended a Victor style 100 FC torch handle with a rosebud multi flame tip. I previously got the little smith torch and it's way too small. Thank you.

 

[goldshark]

I've searched the site looking for the answer before posting this, if I missed a thread with the answer to my question please forgive me. Can someone who is smelting platinum please offer guidance for an oxy-hydrogen torch setup? I went into the Airgas store and they recommended a Victor style 100 FC torch handle with a rosebud multi flame tip. I previously got the little smith torch and it's way too small. Thank you.

You should be able to melt with what you have. Put an insulator under the receptacle you are using, for less heat loss. Preheat the dish to redness. A crucible is not recommended.

 

[Jim Morrison]

You should be able to melt with what you have. Put an insulator under the receptacle you are using, for less heat loss. Preheat the dish to redness. A crucible is not recommended.

Awesome! Would a ceramic fire brick be ok for insulation? Perhaps bevel a little nest in the brick for the ceramic quartz dish?

 

[4metals]

Platinum melting is also frequently melted in Wesgo high back crucibles. As @goldshark said there is also a factor of the heat loss through a crucible that is minimized by insulating fire bricks beneath and often around the melt dish. The sloping back of the Wesgo dish allows the flame to be directed downward at the sloped part of the dish causing the flame to spiral downward around the melt charge and deliver more of it's heat to the metal. Also, due to the high melting point of Platinum, fluxes are not used as they cannot survive at the melting point of the Platinum group metals.

Another consideration is without special equipment bars cannot be poured from molten Platinum so it is typically cooled into a button in the crucible and removed when cooled. Wesgo makes crucibles in the 10 and 20 oz capacity rating, although I will attest melting 20 ounces of Platinum sponge in a Wesco crucible is an acquired skill.

 

[4metals]

Can someone who is smelting platinum

There is a difference between smelting and melting (at least in the USA). What you are looking to do, I assume, is melt refined platinum metal from a sponge into a button. Smelting is more of a refining process where undesirable components in an alloy or ore are removed by fluxing in a melt furnace using specific flux depending on the desired result.