Making 90-degrees bent brass elbows from thin-wall brass tubing is
quite easy and inexpensive and the result is very professional.  Get
yourself some Wood's Metal [eutectic alloy] which can be brought on
the 'Net from many sources.  Wood's Metal melts at a temperature of
only about 160 Degrees F. or 90 degrees C., and will easily melt in
hot water.

Cut the brass tube to the length you want it to be and anneal the brass
by heating to near red hot and plunging into water.  Plug off one end
to the tube and fill the tube with melted Wood's Metal.  Before it has
a chance to cool plunge it into cold water.  This is important as the
Wood's Metal will be soft and malleable.

Then simply bend the tube by holding it against another piece of larger
diameter pipe and bending with your fingers.  Then place the little
elbow in some hot water and the Wood's Metal will melt out, to be used
again.  I made 100 of these 90 elbows in no time at all, when restoring
my Furness pianola which has a Sterling mechanism.

Cheers,
Peter Smyth
Murray Bridge, South Australia

 [ Wood's metal is magical stuff, but it is also toxic, so pay attention to
 [ proper handing and ventilation.  There's an interesting Wikipedia
 [ article: http://en.wikipedia.org/wiki/Wood's_metal
 [
 [ The article specifically mentions using it as a filler when bending
 [ thin-walled tubes, but it goes on to say:
 [
 [ Wood's metal is toxic because it contains lead and cadmium, and
 [ therefore contact with the bare skin is thought to be harmful,
 [ especially in the molten state. Vapour from cadmium-containing alloys
 [ is also known to pose a danger to humans. Cadmium poisoning carries
 [ the risk of cancer, anosmia (loss of sense of smell), and damage to
 [ the liver, kidneys, nerves, bones, and respiratory system. Field's
 [ metal is a non-toxic alternative. 
 [
 [ The dust may form flammable mixtures with air.
 [
 [ A short article on Field's Metal is here: http://en.wikipedia.org/wiki/Field%27s_metal
 [
 [ --Jody