5 Essential Knots You Must Learn for Fly Fishing

This might seem like one of the most intimidating parts of fly fishing.  Crazy names for connecting strange strings called “Tippet” and “Backing”.  It really isn’t all that complicated to learn knots for fly fishing.  Below I’m going to describe where to use the knot and how to tie it.

1.  The Nail Knot – My Secret Weapon

use nail knot for line to backing

use nail knot for line to backing and line to leader

What is a Nail Knot

A nail knot is used primarily in fly fishing to join to dissimilar diameter lines.  The nail knot is very flat and will easily slide through the guides of a fishing rod.  The nail knot fastens by bunching up 5 or more loops onto the joining line.   This bunching of loops “squeezes” down onto the joining line.

Common Uses for the Nail Knot

The nail knot is used to attach the backing to fly line and fly line to leader.  The nail knot excels when joining to dissimilar diameter lines.  The design of the knot allows it to squeeze tighten more as it is being drawn down.  I’ve also used a nail knot to create a loop for loop to loop connections.   One of the negatives to the nail knot is the learning the tying technique.  I’ve found that having a long tag line helps and quickly pulling the knot off the tool helps.

I keep discovering more uses for the nail knot.  Leader to fly line, loops for loop to loop connections and fast snell knots for hooks.  I’m sure that with a little more time I’ll learn another use for this secret weapon.  Using a nail knot tool makes tying easier and opens up more opportunities for uses, I’ve tied this knot without a tool and you really feel like you need a third hand.  For usually around $10 you can get one of these tools.  I RECOMMEND one that can be found at AMAZON HERE -> Tie-Fast Knot Tyer

Strength of the Nail Knot = Strong

This isn’t usually an issue in freshwater situations.  Fly Line typically has a +20 lb core and backing is +20 lbs.  The butt section of a leader is pretty heavy mono +8 lbs.  A knot by definition is going to be weaker than the standing or running line.  Because the nail knot is used on higher breaking strength lines a 30% reduction is still stronger the weakest part of the fly line system which in most cases is the tippet.

History of the Nail Knot

To provide some background for the nail knot, originally the knot used – you guessed it – a nail.  A nail was readily available and primarily used to create a space for the tag end to be pulled through the tightening loops.  Also called a tube or gryp knot it can be tied with a straw, but like I was saying the simple nail knot tool makes tying this knot much easier, plus the tool expands the applications for this knot.

How to Tie a Nail Knot

The nail knot is tied “onto” the fly line.  Meaning that the coils will be wrapped around the fly line.

When using a nail knot tool I tie the nail knot by:

  1. Have 10 inches of tag line hanging out of the U tip of the nail knot tool.
  2. Hook the tag end into the fork of the tool
  3. Wrap the tag end 5 to 8 times around the tool
  4. Slide the tag end through the U of the tool toward the tip.
  5. Approximately 8 inches of tag should be hanging out of the tip of the tool.
  6. Insert the fly line into the tip of the tool approximately an inch
  7. Quickly pull the tag and the wrapping off the tool.
  8. Dampen or lubricate the loose knot.
  9. Pull the tag and running line until knot is tight.
  10. Trim tag and stub of fly line.

Video of How to tie a Nail Knot

 

2. Double Surgeon’s Knot Plus using the Double Surgeons Knot for Tying on Flies

double surgeons use fly fishing

double surgeons for leader and loop for fly

What is a Double Surgeon’s Knot

The double surgeons knot is a fast way to connect to similar diameter materials.  Essential two lines are laid parallel and tied with two overhand knots.  A variation of the knot is a Triple Surgeon’s which adds a – a third overhand knot.

When to use the Double Surgeon’s Knot

Primarily the Double Surgeon’s Knot is used for attaching tippet to a leader.  In my opinion it is more forgiving to different line diameters as compared to a blood knot.  You can also use the double surgeon’s to build a leader by attaching multiple sections of tippet together.  I’ve also used the double surgeon’s knot to make a loop for tying on flies and streamers.  By extending the tag end on the double surgeons knot you can also add weight or a second fly.

Easy to learn, fast to tie and friendly to cold fingers, the double surgeons knot is a must have knot.  It is important that this knot is lubricated when tightened.  Lip balm is a perfect lubricant if your hesitant about using saliva as lubrication.

Strength Of the Double Surgeon’s Knot = Stronger than Blood Knot

In my experience when compared to the Blood Knot the Double Surgeon’s Knot is a little bit stronger.  The down side is that if a double surgeon’s knot doesn’t tighten correctly it can be significantly weaker.  Also the double surgeon’s knot isn’t as straight as the blood knot, which could reduce accuracy when casting.

History of the Double Surgeon’s

The SURGEONS KNOT was named for its use on sutures.  The surgeons knot is able to be tied with tension which is used to pull skin together.  In fly fishing we add an extra throw or double overhand twist, which gives the knot more area to clamp, thus eliminating slippage.  Many tie a triple surgeons, but I find this puts a kink in the line.  The kink usually doesn’t allow the line to straighten completely.  In salt water fishing the surgeon’s knot is used with 6 turns to attach mono to braids – super strong and fast to tie – LEARN THIS KNOT!

How to Tie a Double Surgeon Knot

  1. Lay 4 to 6 inches of leader and tippet side by side.
  2. With the two lines together form a loop.
  3. Pass the leader and the tippet through the loop once.
  4. Pass the leader and tippet through the loop twice.
  5. Lubricate – IMPORTANT!
  6. Slowly pull tight.
  7. Clip the tag ends.
nail knot nipper tool

nail knot nipper tool

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Video Instructions for tying a Double Surgeons Knot – with my secret loop

3.  The Clinch and the Improved Clinch

Where to use a Clinch Knot

use a clinch knot to attach tippet to fly

I’d love to say the clinch knot is the first knot I ever used fishing, but it’s KNOT.  Actually I tied the good old granny knot to my hooks (I was around 6 years old), I can say the clinch was probably my second true knot used for fishing.  This is a strong knot, from what I’ve read it retains up to 95% of the main line strength.  It does have a tendency to loosen or even have the tag pull through.  I usually keep about an 1/8 in of tag off the knot.

I usually tie the clinch with hemostats.  It’s a lot easier on my eyes and if my fingers are cold spinning the loops onto the fly can be difficult.  A little trick I do is to tie small flies onto a length of tippet at home, then for a quick fly change I will snip off the old fly at the leader and quickly tie on the new fly using a double surgeon’s.

Where do You Use the Clinch Knot

The first use for this knot is tying on flies, but this knot is used everywhere:

  • Tying on swivels
  • Tying on leaders onto the fly line loop
  • Tying dropper flies onto the bend on the lead fly
  • Pre-tying tippet onto small flies at home before hitting the water

Double Surgeons Knot Strength = 85% to 95% of Original Material

History of the Clinch

Search as I might, finding the history of the clinch knot has become elusive.  The knots seems to come on the scene with the invention on monofilament in the 1940’s.   As fishermen started using these wonder materials, all kinds of knots appeared.  The Clinch knot is also called the “Jam” knot by some.  I remember in the 70’s Berkley labeled the improved clinch the “Trilene Knot”   This knot is basically an added throw of the tag end through the loop formed by the clinch.  Little know history but a critical knot for tying on flies.

How to Tie a Clinch Knot

  1. Thread tag end through the eye of hook
  2. With 4 to 6 inches of tag, wrap around (twist) main line 5 to 7 times
  3. Loop tag through the small loop formed at the eye onf the hook
  4. Lubricate and draw tight.
  5. Clip tag end 1/16 to 1/8 from knot

Video Instructions for Tying a Clinch Knot with an Easy Way to Add a Dropper

4.  The Duncan Loop / Uni-Knot – draw it down or make a loop

Duncan Loop to tie on fly

duncan Loop to tie on fly

The duncan loop is a slip knot that you can “lock” into position.  The neat thing about this not is once the loop is formed you can slide it into position then tighten or “lock” it.  The duncan loop is mostly used to attach streamers or nymphs with a loop so the fly can swing naturally in the current.  You can use the duncan loop for making a loop in a leader to attach the leader to the fly line in a “loop to loop” connection.

Uses on the Duncan Loop / Uni-knot

Like I was saying the Duncan Loop (also called the Uni-Knot and sometimes the Grinner Knot) is used for attaching the tippet to fly and leader to fly line.  The loop allows the fly to have a little more freedom.  This knot is also GREAT for braided line and gel-spun poly – WET this knot – lube with lip balm or saliva as this knot can heat up the line when sliding into position.

Duncan Loop Knot Strength = 80% to 90% is what I’ve read (I haven’t tested to confirm)

History of the Uni-Knot or the Duncan Loop – was it stolen?

This knot is also called the Duncan loop, after Norman Duncan who developed it independently as a fishing knot in the early 1960s. The knot was popularized as the uni knot by Vic Dunaway, an editor at the Miami Herald, in a 1970 fishing book. … However, in British English it is commonly known as the Grinner Knot.  Very closely related to the infamous gallows knot used to hang folks.

How to Tie a Duncan Loop / Uni-Knot

  1. Thread approximately 8 to 10 inches of tag line through the hook eye.
  2. Pinch the lines together at the hook eye so the lines run parallel to one another.
  3. Circle the tag line back around to the hook eye forming a loop.  This loop needs to be big enough to pass your fingers through.
  4. Wrap the tag line through the loop and around the running line.
  5. Wrap between 3 and 6 times.  I personally stick with 5 wraps.
  6. Loosely pull on the tag line to start to form the knot.
  7. Lube the knot and slide it into position for the size loop you’d like.
  8. With the loop in position pull hard on the tag line, this locks the knot into position
  9. Trim the tag line within a 1/16 of an inch.

Video Instructions for Tying a Duncan Loop

5.  Blood Knot – Tying leaders and closely sized lines

blood knot for fly fishing

blood knot for fly fishing

One of the tougher knots to learn to tie is the BLOOD KNOT, but with a little practice and maybe a cool tying tool the blood knot might become one of your favorites.  This knot is strong, and ties flat and straight.  Perfect and maybe best for building leaders, this also called the barrel knot.  Personally I don’t use this knot a lot, but mostly on those occasions whe the fish seem spooky and long light leaders and tippets are needed.  If I could name a characteristic of the knot I would say beautiful and elegant.

Uses of the Blood Knot

This knot is mostly used for tying leaders or attaching tippet to a leader.  When fish seem spooked and your presentation needs to be delicate and accurate, turn to the blood knot.  The double surgeons knot will usually have a kink/bend in it, but the blood knot will tie straight and true.  This knot is best used when tying lines similar in diameter.  If you tried to tie 0X tippet to 4X the knot wouldn’t hold correctly.

Blood Knot Strength =  80% to 90% I would caution you that the blood knot is easy to mess up, which will quickly reduce it’s strength

History of the Blood Knot

When searching Google, I didn’t find much specifically about the “blood knot”.  If I had to guess the knot started our as the barrel knot and some English Gentleman complained it was hard to tie and yelled “I HATE TYING THIS BLOODY KNOT”.  Ok just a guess……

How to Tie a Blood Knot

This is one of those knots that are easy to show in a video.

  1. Overlap two similar sized lines.  Be careful here because the knot doesn’t like tightening up if the lines are significantly different in diameter.
  2. Wrap or twist one tag end around the other line 5 turns
  3. Bring the tag end back between the two lines at the start of the wrap.
  4. Repeat this same process with the other tag end.
  5. Lubricate the knot.
  6. Pull the tag ends and running lines in opposite directions
  7. Trim tag ends close.

So the tough part about the blood knot is the need for a third hand.  I found an innovative tool to help solve the concern.  Enter the EZ TIE System.  I found this tool while researching blood knots for this post.  Check out the availability and pricing at this link to AMAZON EZ TIE SYSTEM.

ez tie system for blood knots

ez tie system for blood knots

Video instructions for tying a BLOOD KNOT

Enter name and email to for a Chance to win 1 of 25 nail knot/nipper tools.

nail knot nipper tool

nail knot nipper tool

One Rule live in the USA – The Drawing will be on March 31, 2018