I recently made up a batch of quig tools based on Al Klase's design.
I used the same basic materials: K & S 0.040" music wire and 1/16" and 3/32" brass tubing for the jig, and plastic tubing for the handle. Like Al, I soldered together parallel lengths of the 1/16" and 3/32" tubing. That was easy-peasy.
But Al then soldered a length of the music wire to the saddle between the two tubes. I couldn't manage to solder the music wire without unsoldering the tubing. Perhaps I could have made a fixture to hold things together for soldering, but I instead wrapped the bundle of the tubing and the music wire with a length of 26 gauge bus wire. This held everything together while I soldered it.
Al used thick-walled 5/16" diameter plastic tubing for the handle. Based on Al's photo, I think he used Plastuct butyrate tubing, which has an inside diameter of 3/16". I used Evergreen 1/4" styrene tubing for my handle instead. I used slow-cure epoxy to glue the tool into the handle.
The next day I touched up the ends of the tubing with a mill file and de-burred the center of the tubing with some small wire drills.