I recently bought a used Consew 206RB 1 for my leather business. I intend to use it for lighter work like chaps and book covers and the like. I tried to use it a few days ago with 138 size thread. After sewing a couple of inches slowly, the top thread begins to fray and then break. I took it to a local sewing machine shop and after having it for a few days the guy called me and said that the 138 thread was too heavy for the machine.
OK, I'll use size 92 thread. I'm having the same problem. How heavy a thread can I use? Anybody have any idea what might be causing my problem?
Thanks in advance!