My machine (1970s Montgomery Ward) has been having a problem for the past couple of days and I'm trying to figure out what the problem area is so I can attempt to solve it before taking the machine in for servicing.
It sews fine for a while but then tiny loops appear on the bobbin side of the seam. They aren't very big but they allow me to pull the bobbin thread right out of the seam with no resistance.
I thought that maybe I was somehow losing tension as I sewed but adjusting the tension doesn't seem to make a difference. Any help would be greatly appreciated.