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How to Tie a Blood Knot

Also called the barrel knot, the blood knot is a knot that bends. This knot is most advantageous for effectively tying pieces of monofilament nylon line. While tying this knot it is imperative to maintain control of the majority of the line to enable its innate durability.  

The blood knot is actually two clinch knots that are joined together. This knot is actually a fly fisherman’s favorite.  By advancing the number of wraps on either side gives the knot more durability. This article is going to show you how to tie a blood knot; complete with step-by-step photos as an example. 

Steps for Tying a Blood Knot 

Step 1: The first step in tying a Blood Knot is to take two lengths of rope, twine, or fishing line about 6 inches long. 

Blood Knot Step 1

Step 2: Take these two lengths and overlap the ends you want to be joined together.

Blood Knot Step 2

Step 3: Next, wrap one line around the other, at least 5 times.  (Here is where you can add durability by adding extra wraps). 

Blood Knot Step 3

Step 4: Repeat step 1 on the other end of the line; ensuring to use the same number of wraps. 

Blood Knot Step 4

Step 5: pull the two lines opposite ways. The turns will wrap and cluster together. 

Blood Knot Step 5

Step 6: cut the end closest to your knot. 

Blood Knot Step 6

Tips on Tying The Knot

Here’s a tip on how to tie a blood knot with ease in less than 10 seconds.  The secret is using the thumb or one finger to create an open area between each of the wraps. 

The blood knot is more durable, with a profile much thinner than a surgeon’s loop. As you complete your knot, the fatter it becomes an increased likelihood of eventually hitting a snag.  

Variations On Tying the  Knot

Here is one variation or alternative method of tying the blood knot. Just twist and fold over the two ends which are in sync with each other. Do this for approximately  10 to 14 repetitions.  After doing this, proceed to the center of this contortion and form a hole. Bring each end through the hole in a reversed method.    

Whichever manner you choose in tying the blood knot you must ensure the middle is symmetrical. Despite the fact that each twist progresses in a similar order make sure each side is a mirror image of the other. 

Advantages of this Knot

The Blood Knot is one of the easiest knots to teach and learn. It is a most efficient approach to adhering two comparably gauged lines to one another.  

Disadvantages of the knot

There is an enormous amount of dexterity needed to tie the blood knot; notably the primary disadvantage to this knot. If you are tying a fishing line, any possible jamming is not really a concern at all.  There is not a loss to the cut; however, it could pose a concern when using normal rope. The term “Blood Knot” refers to a “double overhand knot tied in a cat- o’-nine tails.”  

History of the Knot

The Blood Knot dates back to the days of sailing. During that time, there was an adaptation of this knot. This version was on which the edges of a whip or “cat of nine tail” was used in the depiction of blood. 

The Blood Knot has also been referred to as a barrel knot. When attempting to use a knot other than the Blood knot, there is a considerable amount of durability lost. This knot has proven to be best for fly-fishing because of how it slowly reduces how wide the casting fly line is. 

The half-blood knot (or clinch knot) is another excellent way to secure your line for fishing to the snap, swivel, or lure.  The use of these two knots in combination is what creates the blood knot.  If you want to know the strongest way to tie your medium-sized hook to a line, use the half-blood knot.  

Uses For The Blood Knot/Loop/Bend

The typical use of the Blood Knot is for the joining together of monofilament nylon lines. 

Survival Situations

Fishermen favor using this knot because it is utilized for the adjoining of two similar lines. The Blood Knot is the best knot to use for fishing.  

  • Fishing: The half-blood knot (also called a clinch knot) is what fishermen use as a means of stabilizing the line for the swivel, lure or snap. The Blood Knot is a must when going fly-fishing. It is used to connect the tippet and the leader. 
  • Hunting: The most common cause of injury or death during hunting season isn’t always because of firearms. Hunting injuries result from using a poorly constructed tree harness. Low-cost tree harnesses often reduce blood flow to the extremities should you fall; this results in blood clots in your arms and legs. In addition, they can impede breathing, and cause you to pass out and possibly die.  The use of a Blood Knot can deter this scenario. By ensuring you have a piece of nylon cord with your survival supplies you can lasso a tree branch (or ladder rung) to give yourself better positioning.  You can then secure the nylon cord by using the durable Blood Knot to enable your secured to the tree stand safely.
  • Camping: You can also use the Blood Knot to ensure your tent is securely in place. This knot will ensure all the stakes are tied down safe and secure. 
  • Other uses for a Blood Knot: Anytime you need to join two lines of similar size together, the Blood Knot will prove useful. What is great about this knot is you can make it as strong as you need it to be.  By adding or decreasing the number of loops you use will make the knot stronger.  This knot is typically used as the ideal knot for fishing. But as we have pointed out, it can be used in any situation. 

Related Knots

Blood Knot Variations and Similar Knots  

Create a dropper rig for fly fishing by clipping one tag end but leaving the other tag end long.

You can also tie a blood knot to a fishing hook with a half blood knot. Tie one half of a blood knot to the eye of the hook using the intersection between the line and eye to pull tight.

Other knots similar to the blood knot include the double fisherman’s knot, the surgeon’s knot, the barrel knot.

Final Thoughts

Learn how to tie a blood knot with rope first.

The process is more difficult with fishing line because of the dexterity required. But, with a little practice, you’ll eventually learn how to tie this important fly-fishing knot quickly and efficiently on monofilament line.

To create a tapered leader for fly fishing, tie a series of blood knots each approximately 2 feet apart in decreasing diameters of line material.