Threading the bobbin
Put metallic thread on your bobbin by hand. If you are using very fragile thread, having metallic thread in the bobbin can help.
The main reason why metallic threads constantly break is that it’s a synthetic thread type. This makes it stiffer especially compared to Rayon, which is noticeably softer to the touch. Polyester is also a synthetic thread, but it is not as stiff as Metallic.
Metallic thread with a lower Tex rating generally is very strong and suited for use in high-speed sewing such as embroidery.
The fraying only gets worse as the thread repeatedly passes through your fabric. To eliminate this problem, cut a piece of floss that is twice the length you want to stitch with, and separate out a single strand. Fold the strand in half, and thread the loop end through the eye of your needle.
We have metallic threads that have a “reflective effect” in daylight, but this is the only thread currently available for NIGHT reflective effects, and for use on a home sewing or embroidery machine.