Greetings guys, I'm at the end of my rope. My mother passed away in July and she was the only person that I knew that had the magic fingers to fix her own, let alone everyone elses, sewing machines. It is a Singer Professional sewing machine, set up on a bench like shoe shops would. I hope someone can help me out here in chicken land!!! What its doing is not catching the thread from the bobbin, then it will gump up the thread on the underside. See, I've tried changing the threading, direction of the bobbin spool, tightened, loosened and prayed to heaven above and almost started a sweat lodge under it! If anyone can give me a clue, I'd truly appreciate it! I truly hate to take it in for repairs if its a simple matter. We have a sewing friend that thought the timing was off. I just don't know. Thank you in advanced for helping out.