Originally Posted by thepolyparrot

I really LOVE them for all my vertical bobbin machines.

I tried them on my 201 and 401 and they don't work, but for the vertical bobbins, they're really magic.

This picture shows the difference with the back of my work - I was quilting some placemats just for practice in small stippling when the washers came in an order. I popped one in and the difference was immediate and pretty obvious. :) The back of the one on the right is after I put the washer in.

The difference is even more dramatic in larger designs like feathers and flowers.