I have been making jewelry from jump rings from a number of years. I
have progressed to making everything from Alloying silver/gold for
solder or different carrat values, and drawing all my own wire. My
problems are all derived from the casting of the bars. I know to
watch for anything that can fold into a cast as I am working it on
the rolling mill, but regardless of how often I anneal the wire, I
am getting cracks. When I coil the wire and cut the coils, it’s not
a big deal as I remove the damaged rings adn amounts to less than
5%. But it does make the wire hard to handle and such tasks as
weaving are impossible. When I say hard to handle, It can be like
razor wire at times and I have bled more than once.
When I am finished casting a silver bar, it’s surface looks very
smooth with large snowflake pattern on it. It looks great, but never
fails to crack, at least partially, during the wire making process.
I do heat my mould, use oil and borax. If the problem is the metal
is too hot (I try not to boil it), the question is how to get the
"Right" time to pour. I wait until the molten pool can have the heat
removed and swirl for a second, then I pour through the torch flame
into the mould. I have read books on casting, but am having trouble
getting rid of this problem. Gold seems to have much less tendancy
to crack, but due to it’s cost and my lack of sales, silver is my
most used medium.
Any tips would be much appreciated.
P.S. I am a hobbyist. I make 1 or two pieces a week and have never
taken this is school.