I gave my daughter one of my Featherweights some time ago. Today she brings it over complaining that it is not making stitches and was "clunking". So I went through the usual.
1. Did you read the manual???
2. Is it threaded correctly?
3. What did you do with since you used it last.
Answer to the first two questions was "yes". The answer to the third question was "I changed the needle". My answer was "is the needle in correctly?" She checked and guess what? The needle was not in correctly. That needle must be installed flat side to the left. I told her that she has a manual for a reason, she needs to refer to it. Lesson learned.