I recently purchased a singer promise sewing machine. I wanted to sew my flour sack towels into inserts so that I would no longer have to fold them to stuff my pocket diapers. I was able to sew about three into inserts. Then my needle broke two times in a row. Now mind you, I only had three needles to begin with! I was hurt. I have no idea why this has happened. The only thing I can think of is that my needles are not strong enough to sew through the thickly folded flour sack towels. I have just ordered some new needles in different sizes to see what will work for different materials. Wish me luck!!