ok, here we go....

This is quite a large shade. 28" Diameter.  My mold is made of plaster and the question was, whether or not using tacky wax is a good  idea. I think, the best solution is to just use it in strings, placed as support under the horizontal rows and remove it right after they have been tacked with a bit of solder. This will enable me to lift the shade off the mold easily in the end, avoiding the mess on its inner side etc...