There are a host of little changes, notably the needle plate. I have discovered several different needle plates on the later WW 9. A big difference is the bobbin case. The last 9W used a FW bobbin--much easier to find than the bagel bobbins!
Originally Posted by skaduzy
What is the difference in a Wheeler and Wilson D9 and a W&W W9? Just wondering? Mine is the W9.