I used the same method as twining the ends of handlbar tape only using old copper telephone wire. I followed the steps you will see on this site for tying.
http://www.rivbike.com/
When you open this Rivendell page, click on the ball of twine and there are pictoral instructions on how to finish off a handlebar. I just miniturized the process and it worked like a charm. I did a lot of these ties on my hi wheel bike and they are still intact and look great. I did solder them but did not use any epoxy as you mentioned.
My concern for epoxy is that it might trap flux or other undesireable elements in the work. Once I was done with the tie and solder, I washed the area with soapy water using a tooth brush, then clean water and finally acetone to remove any solder residue or moisture.
Ray Homiski
Elizabeth, NJ USA