When is an M bobbin case not an M bobbin case? When it’s made by different manufacturers for different machines! Currently, there’s a discussion on the forum for the owners of sit-down models of quilting machines about the M bobbin case for the Handi Quilter Sweet Sixteen/Babylock Tiara, and one of the members posted a picture of the black spring she was told to remove to use the pre-wound Glide bobbins. The problem is that my bobbin case DOES NOT have this black spring and I suspect never had it as I can’t recall seeing it. (Update: Newer Sweet Sixteens have bobbin cases with the black spring.)
So I took some photos of my only bobbin case — the one that came with my Sweet Sixteen machine back in April 2011 — so that I’d have them on hand for future reference. I took several photos from different angles.
The only ‘spring’-like thing INSIDE my bobbin case is the flat metal piece that’s screwed into the housing — you could not remove it without first removing the screw. On its inner side, this flat metal piece has a straight edge, then sweeps into a scythe-like curve. Also, note the width and shape of the bobbin case opening (not the ‘fingers’ surrounding the opening, but the opening itself) — it’s a sort of skinny ‘D’ shape.
As a result of this discussion, I went searching for M size bobbin cases on the internet and found that there are all sorts of variations of these. Below I some photos I grabbed from the internet. Notice the shape of the opening, the ‘spring’ shape, and the black spring (in some cases), and even a ‘pigtail’ spring. They are all a little different to the bobbin case I have. So buyer beware! If you purchase any old M size bobbin case from the internet, it may not be the correct one for your machine!
Tin Lizzie
Pfaff
Gammill
Japanese A1 long-arm
Rhonda Bracey: At Random 
It is quite an eye opener since you are always told that the SS and Tiara are identical other than name branding. Wonder what else is different!
Off to check mine…………..will report later!!!!!!! Super interesting!!!! I haven’t been on the forum in quite a while. I had better revisit!!! Thanks for the post!!!!!
Yup, mine is just like yours!
The bobbin “spring” most have referred to is shown in a number of the photos. Look at the very last one – it is that black squiggly thing in the bobbin. It is designed to minimize bobbin overspin on machines. The alternate name I have heard is “anti-backlash spring”. It is not attached, but just loosely sits in the bobbin case under the bobbin. I had one in my Sweet 16 bobbin and I had one in my multi-needle embroidery machine. I never found them helpful, even on non-magnetic bobbins. My S16 happily runs SuperBob pre-wounds and the embroidery machine (which generally runs Filtec magnetic pre-wounds) doesn’t need it when I run regular bobbins I fill myself.
I understand some machines really do run better with these things, so if folks are having a problem with backlash/overspin, they can give it a try.
Pam
Yes; mine for the Tiara is like yours Rhonda. I did get one on line…well my daughter-in-law bought it for me as a gift….it had a little t like spring and I wouldn’t use it….just in case of problems. Things work good the way they are right now…lol. Thanks for your info
Thanks for the heads up a
Harder than finding the right case is finding the correct backlash spring. Thanks for your post!