Funny you should mention this...A couple of years ago, my old favorite Kenmore from the 70s started making a knocking noise when I sewed. When my DH found out it was 30 years old, he decided I needed a new machine, which he bought for Christmas. I haven't used the Kenmore since. Now I'm thinking that Kenmore just needs a good cleaning and oiling, because years ago I never really thought to oil it regularly, and it probably has years of built-up gunk around the feed dogs. It's on my list...