singer touch and sew model 648 bobbin
I have a perfect Singer Touch and Sew model 648, circa 1970, that has been a fine sewing machine my whole adult life. Just recently, the little oval white button with the red concentric circles (dot) that you press to the left to engage the bobbin threader has frozen and it won't move. Thus, I can't thread the bobbin. I've called a sewing machine repair near me, they couldn't help; I've looked on-line with no luck, and I'm hoping someone out there will know what to do...Thanks.