I have a Singer Curvy 8780 which takes 15J bobbins. I emailed Singer to ask if I would use an L prewound bobbin. They replied that Singer machines can't use prewound bobbins, only 15J. Has anyone who owns a Singer used prewound bobbins? TIA

They did not work in my Singer.

Thanks for the reply. Hopefully, my Brother can use the ones I ordered from Connecting Threads.

They work great in my Brother and my Babylock!

Did Singer say why the pre-wound bobbins won't work? Interesting.

No, they gave no reason. Just said to only use 15J bobbins. I am curious, too.

I went back to your original post and you don't say whether the pre-wounds are on a 15J bobbin?? Different machines, different bobbins, even though a lot of them look alike. I know my Viking will only take Viking bobbins so I haven't been tempted to try the pre-wound.

Were the pre-wound a better buy or, are they just convenient? (Nothing wrong with convenience, that's for sure!) _:-)_

Singer even sales pre wound bobbins

I find the prewounds are truly convenient and also hold far more than the bobbins I wind. I got a killer deal on ebay a couple of years ago and bought something like 2000 of them for my embroidery machine.

Two Thousand of them? Wow, you must embroider up a storm. How many have you gone through?