From your description of trying to mount a half-round wire on top
of a "green wax ring", I'm wondering if you'd be further ahead by
actually working with metal wire and sheet stock instead of wax.
Depending on the complexity of your design, often working directly
in the metal and soldering the components together is the fastest,
and cleanest way to do it.
Don’t forget that by making your wax model, spruing, casting, and
then cleaning and polishing that cast model, you are in effect making
it twice… once in wax, and then the filing, sanding, and polishing
the entire casting to finish it.
In our studio, we don’t use very much soft wax ( it’s such a pain to
work with, and impossible to hollow out) but use mostly carving
waxes. Casting we generally save for projects we cannot fabricate in
Back to your original question though. To adhere the soft waxes
together, I’d try either a wax solvent or super glue.