When soldering the silver, since your links are pretty large, just
use soldering arms (third hands) to isolate the wooden links from the
silver link. So you’ll have the 2 wooden links held by one arm,
another arm holding the silver link with the joint uppermost, and the
silver link is not touching the wooden ones at all. Solder the links
in assemblies of three (2 wooden ones, one silver), then solder these
assemblies together with more silver links.
To remove the smutz from the silver, either brass brush the silver or
use a little fine pumice powder. Do they sell Bon Ami scouring powder
there? This is pumice powder with a little soap, but no chlorine.
Cheap, works great.