Knots for Joining Lines

What is the best knot for joining lines? This is probably one of the top in the list of "most asked questions about fishing". There are at least 10 knots out there claim to be efficient in joining lines, but out of all these knots, only 2 have proven themselves to me throughout my years of fishing.

Since the first time I had to join lines many years ago, my go to knot has always been the Double Uni Knot. This knot is very easy to tie and the result is a very strong knot. However, I have realized over the years that there are very specific guidelines that need to be followed in order to ensure this knot never slips. The guidelines are as follows:

For all mono lines(or the mono side of a mono-braid connection):

50+lbs use 4-5turns
30-40lbs use 5-6 turns
20-25lbs use 7-8turns
10-15lbs use 8-10 turns
below 10lbs lines use at least 10 turns.

For braided lines I always do a fixed 20 turns.

Here's a link explaining how to tie the knot: http://www.fintalk.com/fishing-knots/double-uni.html

Another suggestion is to use a lighter to singe the tag ends of the knot rather than just simply cutting it, the melted end will prevent the knot from slipping. Here is a picture of a Double Uni Knot.



After switching exclusively to braided/PE line ~2years ago, I realized that there was a way to strengthen the knot further. Someone else probably invented this somewhere out there, but I figured it out for myself about a year ago and I call it the Improved Double Uni Knot. For this knot you begin with a standard double uni knot, with the addition of tying a 4-6 turn half-hitch knot with each tag end for added security. This is similar to the half hitch that you would tie on a bimini twist. It is important to note that this new addition of the half hitch works mainly on braided/PE lines due to the fact the the thin diameter allows for a neat finish.

So that is the first knot I use for joining lines. The second knot I use only came to my attention about 6 months ago, it is the FG knot. I have come to realize that it is just as efficient as the double uni knot which the exception that it has a much lower profile and hence works better with braid to mono connections, especially where the mono side is significantly thicker than the braided mainline, as is the case when attempting to attach shock leader.

The FG knot works on the exact same principal as the Bimini Twist, but instead of wrapping the line around itself to form a loop, you are wrapping the braid around the leader. The secret to the knot is the sheer amount of friction produced by the 20-30 wraps around the leader, which tighten even more under load, creating more friction. This results in a knot that gets stronger the tighter it is pulled, amazing stuff. And like the Bimini Twist, it is finished off with a bunch of half hitch knots. Below is a picture of a finished FG Knot.



A great instructional video of the knot can be found here: http://www.youtube.com/watch?v=2e9XgPsWZao

There are a few scenarios when talking about joining lines, and they can be very different depending on the scenario and hence, the knots required might differ too.


Joining Mono to Mono of equal diameter

Knot to use: Uni to Uni knot, aka the Double Uni knot.

Joining Braid/PE to Mono, where Mono is the backing

Knot to use: Double Uni Knot or FG Knot

Joining Braid/PE to Mono, where Mono is used as leader or shock leader

Knot to use: FG knot is prefered, Double Uni Knot works too

Joining Braid/PE to Braid/PE

Knot to use: Improved Double Uni Knot.