The Strongest Knot for Joining Fishing Lines Together! How to tie two fishing lines together is a question many anglers ask. Anglers often need to tie two pieces of fishing line or cord together when the main line breaks, or when tying a leader or shock leader to the main line. When fishing, you have to tie thinner fishing lines to thicker ones, and tie together fishing lines made of different materials. Double slim beauty knot - it's almost universal. The knot can even be used to join lines of different diameters, with the exception that the smaller diameter line will require more turns. 00:00 The Strongest Knot for Joining Fishing Lines Together! 02:40 double slim beauty knot Every self-respecting angler should know how to tie two lines together if necessa