I thought my Husband was the only one who didn't read manuals.

I get the same stitch with either.

I also have a Brothers sewing machine. I use both. The only thing I have found my machine will beep when I am low on bobbin thread with the plastic bobbins and it will NOt beep if I use the metal ones, otherwise it works just fine as long as its the same size (15)

Hi David,
The place that I bought my Brother sewing machine says if it came with plastic that is what you have to use. The metal or plastic will affect the tension. I don't think it will cause any damage to the machine. Just make you crazy with the tension adjustments.

At the prison, we use Brother machines & use both metal & plastic. HOWEVER - check your metal bobbins as some of them are loosly made around the center hole so that your thread gets caught on flange of the piece of metal.

I believe all you have to do is make sure they are the same size. That is what my manual said. Especially on the height. I used different bobbins without thinking and ruined my machine.

I have an old Singer that came with metal bobbins. When i bought it though the lady had a plastic one in it. The osmg (old sewing machine guy) here said he actually preferred the plastic ones.

mine are also 15....I would call someone and ask...I was under the impression, you could not interchange....maybe I am wrong though.

I had my Brother cleaned and I was told by the serviceman who worked in a sewing machine factory that the metal bobbins will chew up the plastic bobbin case.

LOL David!!! My husband is always trying to get me to read manuals. I can't wait to show him your post!!! I read the manual when I absolutely MUST!!! The "aha" moments are too much to resist and are such a thrill when experienced! My husband's response: "The manual said it would do that."