Historically the uni knot was known as the Duncan loop after the man who came up with it in the 1960s, Norman Duncan. It’s a relatively new knot and has always been a fishing knot and isn’t used outside of fishing to my knowledge.
How To Tie A Uni Knot
We’ll run through the steps of how to tie a single uni knot to a hook, to begin with, and get into making a loop and a double uni knot later on.
To begin tying a uni knot, take the tag end of your line and thread it through the eye of your hook and pull it down the main 6 inches or so. Then fold the tag end over towards the eye of the hook creating a loop and a kind of double main line.
Creating the loop is the most important part of tying this knot as without it the knot does not work.
Now take the tag end and wrap it around the double main line but within the loop you have just made, not going over it but through it. Continue to do 6 or 7 turns with the tag and be sure to finish coming out of the main loop.
Now wet the knot and pull the tag line so the knot closes around the main line. You can then slide it down to the eye of your hook and pull the end of the line again to tighten it down. Then trim the ends of the line and you have tied a Uni knot
If you want to tie the uni knot with a loop so it’s not against the eye of the hook simply tighten it against the leader line at your desired loop size instead of sliding it all the way down to the hook.
Here is a video explaining how to tie uni knot.
How strong is a Uni knot?
When tested, uni knots have around 90% knot strength. 90% knot strength is great and it means it will break at 90% of the lbs test line you’re using. So if you’re using 10lb line, the uni knot will break at 9 lbs of pressure.
Is the Uni knot easy to tie?
Yes, the uni not is incredibly quick and easy to tie. With some practice, you can get it done in under 30 seconds and get back to fishing.
What is a Uni knot used for?
The unit knot is most used to tie a lure or fly onto a leader line, either cinched down to the eye of the lure or fly or with a loop to allow the lure or fly to swim better, which some people may like more, myself included.
You can also use it for tying your line to the spool of your reel as long as you tighten it enough against your reel so it does not slide up and loosen.
What is a double Uni knot used for?
A double uni knot is used to join two lines and it works with both two braided lines, two mono lines, and to join a braided line to a mono line. The double uni works very well and is one of the best options for making a tapered leader.
See also our post on How To Make A Tapered Leader here for a full guide on making a tapered leader.
Is a double Uni knot strong?
Yes, a double uni knot is very strong, even stronger than a normal uni knot.
How do you tie a double Uni knot?
Tying this knot is very similar to the steps above and is also featured in the video above. Take the end of each fishing line and overlap them by 6 to 8 inches and begin from the middle of step 1 above, creating the loop to thread the line through.
You’ll then wrap the line around both of the two lines you’re joining. Now you have to tie the knot twice, hence the name, tying it once with the end of one line, and tying it once with the end of the other line.
Once complete you will have two uni knots that you can slide to meet each other. They hold very well and are know to to be used for large species as well as small ones too.
Check out our page here for a full breakdown of all the fly fishing knots you need to know.