Note: most tubular track is steel, with a very thin galvanized coating. The solder will adhere well to the galvanize. If you remove the galvanize, the project becomes much harder. A careful clean, plumber' soldering flux might help. I was able to solder copper wire to this steel, part of a turntable.
Also these brass washers to the turntable shaft. Map gas /propane torch was used.
Solder to the bottom of Gargraves, with Solid14 ga. wire leads. A couple of very old Weller Soldering guns. 
