Be sure to use the right kind of thimble with the Aunt Becky. Here is the developer's website that shows the thimble:
http://jeansimpressions.com/
I think the thimble needs to have the outer ring and fairly deep "dimples". I didn't see this thimble at Connecting Threads, but a Google search showed a number of sites selling it for about $8 plus shipping. And, of course, as a hand quilter you may already have a suitable thimble on hand. :-D