I melted my first buttons tonight. We noticed some cracks in the melting dish after the first melting. It held together for another round of melting. Is this normal or should I get a new dish? We tempered the dish for a long while until it creaked and then heated it some more before adding borax and the gold. What went wrong?
Cracks in the melting dish
- Thread starter skyline27
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Noxx
Well-known member
It's normal 
It happen to me all the time.
It happen to me all the time.
Skyline and Noxx,
If you are in a cold weather area, low outside temperatures can cause the dishes to crack from thermal shock if cooled or heated too quickly.
Steve
If you are in a cold weather area, low outside temperatures can cause the dishes to crack from thermal shock if cooled or heated too quickly.
Steve
Noxx
Well-known member
Maybe... but I don't think it affects anything...
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Jewelry supply houses used to sell two different types of clay dishes. One of them was a pale brown color. They are prone to cracking, even when well tempered. I suggest you buy only those that are made of a white clay. Temper well before introducing excessive heat, and coat (interior only) with a thin film of borax.
If your melting dishes sit for considerable time before re-use, it's a good idea to dry them (it) before introducing a torch. I used to place mine on one of the burners at low heat for a while. Never lost one to cracking by that method.
If, by chance, you're using a cupel instead of a true melting dish, I suggest you lose the idea. They won't provide anywhere near the service life of those nice white clay dishes.
You could guild the lily and buy the round melting dishes that GSP has mentioned before, but I found them unnecessary, and expensive in the scheme of things.
Harold
If your melting dishes sit for considerable time before re-use, it's a good idea to dry them (it) before introducing a torch. I used to place mine on one of the burners at low heat for a while. Never lost one to cracking by that method.
If, by chance, you're using a cupel instead of a true melting dish, I suggest you lose the idea. They won't provide anywhere near the service life of those nice white clay dishes.
You could guild the lily and buy the round melting dishes that GSP has mentioned before, but I found them unnecessary, and expensive in the scheme of things.
Harold
socorban
Well-known member
You want some great dishes, check out this site below.
http://www.contenti.com/products/casting/170-710.html
Many dish styles and tools, all at great prices. I directed you straight to the good average sized dishes.
http://www.contenti.com/products/casting/170-710.html
Many dish styles and tools, all at great prices. I directed you straight to the good average sized dishes.
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- Feb 25, 2007
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skyline27 said:
It's been years since I last made any purchases, but jewelry supply houses used to sell melting dishes under the trade name Vigor. They come in various sizes, so you can pick one that is appropriate for your needs. I used the large one primarily, and could melt something like 20 ounces at a time. Too big is better than too small, so don't be timid about buying the largest size, or the next smallest one. These dishes look very much like evaporating dishes (egg shell white in color, not tan), but with thicker walls. They're a wide, rather shallow dish, perfect for torch melting small lots of non-ferrous metals.
Sorry I'm not more help---I've been out of refining for about 13 years now and no longer know what is available.
Harold
