I recently bought this machine second hand from a garment business who's owner also repairs and sells machines. After some stops and starts I got a hang of it and have sewed a few bags in canvas and leather. But there has been a reoccurring problem which now is making it impossible to sew more than a 12 in. seam before the top thread breaks. As far as I can tell, the bobbin thread is just too tight, and increasing the top thread tension to compensate just brakes the thread. and adjusting the spring on the bobbin case is moot. The thread spools out of the bobbin fine while I'm holding it, but once in the machine, the tension is far too high and is somewhat jerky when I pull on it. I've already gone through the manual, adjusted the timing, the hook/needle spacing, the needle/feed dog spacing and oiled everything, but same problem persists. Bobbin thread seems to be getting squeezed between the bobbin case and the hook mechanism on its way out of the needle plate. Any help is greatly appreciated, I was looking forward to a productive day but so far have only been successful in frustrating myself! Thanks
edit: also sometimes the thead will fray to about half it thickness, and bunch up behind needle before braking. Makes me think there is some other issue going on. I sewed an entire bag with slightly thicker thread, with the same needle. I don't know why it would stop working at this point.
