At 06:57 PM 2/13/05 -0800, you wrote:
>What is the best type of bronze to use for boiler bushings on guage 1 live
steamers, and where is the best place to buy it? Thanks
>Jim O'Hearn
Jim,
The preferred material is phosphor bronze, and while there are a
number of "phosphor" bronzes one of the most commonly stocked ones has an
alloy designation of C-510.
A workable alternative is 660 bronze which is a continuous cast
bearing bronze usually sold in 13" sticks at any good bearing supply house
or industrial supply. Even though it has a very small % of lead I use it
for larger (5/8"+OD) bushings and it works just fine.
Henner is of course entitled to his opinion but cutting decent threads
in bushings, regardless of material, is not the point. A very nice thread
can be coaxed through a copper however the greatest need, and the primary
purpose in using bronze, is to retain the fullest and strongest thread form
possible for as long as possible. Fine threads in a malleable material
such as copper are easily damaged or stretched . . . in other words they
"deteriorate" much faster. The reason that phosphor bronze is preferred is
that it cuts and holds threads like mild steel yet is completely compatible
with copper and silver solders as easily as copper.
Regards,
Harry
