I am wondering which type to buy. Does it depend on the sewing machine or personal preference? TIA

I was taught that the choice between cotton and polyester thread depended on the fabric you are sewing with.

Polyester thread is stronger than cotton and can put stress on it, and possibly cause wear and tear, so I was taught to use cotton thread to sew with cotton fabric.

I don't used pre wound bobbins so I don't know if it would depend on your machine or not as to which you chose.

Thanks for the response. I think I will stick with cotton. That's the way I was taught years ago.

some machines cannot use the prewounds at all due to differences in the size of the bobbin case, so you need to check to see if you even can use one. As far as type of thread, you'll see folks on both sides of the fence, so you can do whichever you want. I use mainly cotton, but often use a poly blend if I see a color I want to use in it. I've heard that the cotton wound poly threads are very good because the poly core provides strength while the cotton outer layer provides the protection for cotton fabric. I rarely, if ever, use straight poly.

Most all bobbin thread is poly or nylon. I really like nylon thread for bobbins. I can get twice as much on a bobbin and it sews great. Superior Bottom Line thread for quilting, embroidery, bobbin, binding, and applique is lint-free polyester. Sew Fine by John Flynn is poly. Sew Bob bobbin thread is nylon.

I found if you use cotton with a polyester fabric, the thread will be worn through. So match the material with the thread, is my idea. And it's a free one!

Blessings,
Ruth

I like using cotton. I guess I was just taught to use cotton on cotton.