What it does: The blood knot is used for joining two lines of similar thicknesses.
Why it’s useful: An easy knot with a relatively low profile, a blood knot can run smoothly through rod line guides, whereas other comparably strong knots might get stuck. However, be advised that a blood knot will reduce overall line strength by around 40%.
How to tie it:
1. Cross over the ends of the lines by 6-8 inches and twist one of the lines 5 times (or more) around the other.
2. Bring the end back through the opening between the two lines, then repeat with steps 1 and 2 with the other end of the same line.
3. Make sure the ends are pointing in opposite directions after you pass them through the opening, then pull.
4. Trim the ends, and there you have it… a blood knot.