Silver soldering copper to bronze

Jewelry Discussion
1

The bronze dogs on the power feed for my 18" Highland Park rock saw
are starting to slip. I can order new ones for $120 a pair. I would
like to try and repair these to get a few more miles out of them.
Using a spring, they grip on to a 1/2" threaded rod that turns thus
pushing the saw vice into the saw blade. My thought is to file the
dogs where it grips the threaded rod smooth, take some 10-12 ga
copper sheet and bend it to match the half round places I filed
smooth, and then hard silver solder them in place. Kind of like
adding a bushing to the saw dogs.

Since bronze is copper and brass I’m thinking the hard silver solder
will hold well. Anything I should know about silver soldering copper
to bronze? I’m thinking of using paste flux and maybe a squirt of
batterns too.

Rick Copeland

2

Hard solder works just fine with copper and bronze. As does the
normal paste flux such as EasyFlo.

Incidentally, bronze is not copper and brass: bronze is an alloy of
copper and tin, and brass is copper and zinc. Small amounts of other
metals are added to get specific properties.

Regards, Gary Wooding

3

Paste flux will do fine no need for anything else that is what they
use for silver soldering copper pipe in air conditioning. I used to
work in that field 40 + years ago,

4 
Since bronze is copper and brass...

Rick,
bronze = copper + tin;
brass = copper + zinc.

However, hard silver solder should work with either of them.

Judy Bjorkman

5

My thought is to file the dogs where it grips the threaded rod
smooth, takesome 10-12 ga copper sheet and bend it to match the half
round places I filed smooth, and then hard silver solder them in
place.

Then you plan to make copper threads for your saw dogs. I think that
you will find that copper will not last nearly as long as the
bronze. You couldsolder bronze sheet on the saw dogs, or you could
skip the filing step andweld bronze directly to the worn out threads
on the dogs. Buy bronze brazing rod at a welding store, then use a
small oxy-acetylene torch to weld the bronze rod to the bronze saw
dogs. After the welding, clamp the dogs together, then drill out the
hole so you have smooth sides, then tap new threads in your repaired
saw dogs.

Sounds nice, but… I have never done this myself, so who knows how
much trouble my advice will bring you. :wink: