Been away a while. Have been trying to get my Singer 111W155 working. The thread gobs up on the underside of the fabric. One local poster said she had a chip out of her bobbin holder, and it caused gobbing. I'm going to take the bobbin holder out tomorrow and check it all over. It looks like you should put the bobbin holder all the way down into the hole for it, then align the long screw into the keyway or flat part of the shaft, and the short screw into contact with the shaft on the round part. But don't know if I should bottom it out or leave it up a bit. You can't leave it up too far, or it will hit on the throat plate. Still trying to find a local mechanic who can tune this up, but no luck. I need to take it to Las Vegas, but that is a big deal with the stand and all. I am going to call the store and see if I can just bring the head.
Ideas or sites where I can get the tune up info would be appreciated. I have already downloaded the manual, but it talks in some terms I don't understand. But I'm working on it, and slowly getting there.
Steve