I am teaching a quilting class on Saturdays at our church. Last class one lady kept having problems with thread bunching up around the bobbin holder. I asked her 3 times if she had rethreaded everything. She said yes. I finally did it myself, and I found she had the bobbin in backwards. I showed her the way it HAS to go in..and she answered she "didn't know" it had to go in that way.