What you're trying to do can be tricky and butane may simply not be
hot enough to get it to work. Keep in mind that once you add a piece
of chain or metal to the piece, you've added a relatively huge heat
sink - the way that silver works, you have to overcome that in order
to get the second end to ball up.
By using oxy/propane or oxy/acet, I've accomplished this by simply
getting that end of the silver REALLY hot, really fast... let it ball
and get the heat off of it.
If you're using any type of stone bead, or a bead that's not metal
with a melting point higher than silver, you'll also need to use a
heat sink to protect the bead (such as keeping it under water or
wrapping in wet tissue paper) while you're balling up the wire, which
adds to the heat sink problem.
I assume that threading the ball onto the other end of the silver,
or some other type of cold connection to it isn't an option?
Hope this helps!
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