Monofilament cord is a thin, translucent material used for products like fishing line, beading cord and fibre optic light. Though in many ways it functions well as an extra-strong replacement for string, monofilament is rigid and smooth. This makes it difficult to tie secure knots, especially with a thicker and stiffer cord. For projects like jewellery making or fishing that require tight knots, give yourself added leverage and security by tying with the help of a pair of pliers.
Bend the monofilament at the point where you want the knot. Fold the cord into a loop and pinch the circle tightly between your thumb and forefinger to kink the cord at the apex of the loop. This will direct the knot to that point and create a burr in the cord to make it more difficult for the knot to slide.
Tie the knot in the cord. Slide the loose, forming knot toward the kinked point on the cord before pulling it as tightly as you can.
Tighten the knot with needle-nose pliers. Grip the cord at its ends. Use one pair of pliers at each end if you have two. Otherwise, grip one end with your fingers and the other with pliers to give it a good tug, then switch and tug the other end with the pliers. Pull until the knot is tight enough to not unravel itself or loosen when released.
Repeat steps 1-3 for any additional knots you want to put in the filament.
Trim the tips of the monofilament with scissors to remove the areas that the pliers bruised.