4- and 8-inch Magnetic Copper Butt-Weld Backer Set
Product Review (submitted on March 20, 2012):
Works excellent as a backer for plug or butt welding. I produced very good plug welds as a beginner after using these practicing for about 10 min. The magnets suck though. They lost their hold as soon as the copper got warmed up. I just took another magnet & backed them up or would clamp them in place if needed. A bit pricey though for just a couple of peices of flat copper. Not much to manufacture after all. Certainly the cost isn't in the magnets used. Only negs are price & magnets.