Fish line on eyeglasses is actually a thin piece of clear nylon string called eye wire. The nylon line holds lenses into a semi-rimless, also called rimless, eyeglass frame. The eye wire fits into a thin groove on the edge of the lens. Over time, the nylon becomes discoloured or brittle and needs to be replaced. You can remove the nylon eye wire on rimless eyeglass frames in a few simple steps.
Pull the nylon eye wire away from the frame with the point of your needle-nose pliers. You may also use a paper clip, fully extended and unbent. Force the end of the paper clip between the frame and the nylon eye wire -- and push the nylon string out -- to stretch it away from the frame. Be careful not to crack or chip the lens.
Snip the nylon eye wire using small scissors or wire cutters. Be ready to catch the lens, as it will most likely come out of the frame. However, sometimes the lens stays in place. Take the lens out of the frame and set it aside.
Remove the rest of the eye wire from each side of the frame. The line is held in place on each side, by a small knot. Once you cut the eye wire, you can easily remove each side. Push the nylon wire gently toward the frame to loosen the knot, which should pop out the other side of the frame -- enough to grab on and pull it.
Use ribbon to remove the lens first, then cut the nylon line. Slide a two inch piece of ribbon between the lens and the nylon eye wire. It may take several attempts to feed the ribbon under the line.
Hold both ends of the ribbon, after you have fed the ribbon in between the lens and the nylon line. Pull the wire away from the lens.
Remove the lens from the frame, and cut the nylon with scissors or wire cutters. Remove the eye wire from the frame. Push the nylon wire gently toward the frame to loosen the knot, which should pop out the other side of the frame enough for you to grab onto it.