I have an LPG torch and this is the only one I am authorised to use
in my studio as there are restrictions owing to the fact that it is
in a heritage listed building. I have tried in the past, and failed,
to ball the ends on pieces of sterling silver wire.
My technique was to set up the flux dipped wire so that it would
hang vertically from a third hand and then heat first the entire
piece of wire graduating to concentrating the heat at the end. It
took a long time for the end to melt and when it finally did the
"ball" was messy - porous and usually pulling to one side. I am sure
poor technique (being a beginner at this) didn’t help but the strange
thing is that I was able to get near perfect balls performing the
same activity on pieces with brass wire.
The diameter of the wires I was using were 1.0mm and 0.6mm. and
ranged between 5 and 10 cm in length.
I am wondering if I might have more luck with a flame that has
oxygen or air in it and is thus hotter - I think the length of time
it took to get the wire to melt probably meant that all the flux was
well and truly spent and the surface had oxidised by the time it did
melt. (I finally completed that first project by melting jump rings
into balls and then soldering them onto the wire ends - in the end it
was the only way to finish on time).
Anyway, I am going to be doing another project soon where I would
like to be able to ball the ends of the pieces of wire and am not
sure how to go about it - I can’t upgrade my current torch - that is
a restriction placed on me by the building I’m in. I’m wondering
whether it would be worth trying to learn to use a blow pipe and
spirit lamp to do this.
When I was at college we used torches that had natural gas and air
and I seemed to have so much less trouble using them… this is why
I’m thinking the blow pipe might be the solution - using a flame that
operates on the same concept and managing to get around the rules of
the building my studio is in at the same time.
Thanks for your advice.