FG Knot Helper (Fishing knot)

While searching for the best line to line knot, I discovered the FG knot. It seems it's the strongest knot to tie fluorocarbon to braided line. 

It's not a simple knot. It takes a while to get good at but with a fishing trip coming up quickly, I needed something to help me get good at the knot quick. 

While there are products online you can buy to help, I have a hard time parting with money. (I'm cheap!) 

I was surprised that there wasn't one on here already. I did find one by ABCass11 on Instructables that required metal work and rivets, etc. This design is based on that one with a bunch of improvements taking advantage of 3D printing manufacturing. 

This video shows how to use the purchased tool to tie the knot, but I'm sure you can make the leap to see how the one I provide here subs in.

https://youtu.be/D99B11KRDGQ?si=AZyo1ywM8Hv4Qj7a

There are two washer looking models here (gripper.stl and gripperinner.stl). One has a raised portion around the centre hole (gripperinner.stl). The other (gripper.stl) has a centre hole that is large enough to go around the gripperinner.stl raised portion. This is so the line you put in doesn't get cut by the bolts that run through the tool.

I printed these grippers in TPU to make them a little softer for the line. 

The larger 3 holes will take a 1/4-20 bolt. The head gets locked in the print so you can just tighten the nut without having to hold the head of the bolt. I imagine there may be some people that would like metric versions of this. If you are one of them, feel free to ask.

I made grippy knobs (1-4-20knob.stl) that are designed as a nut trap for the 1/4-20 nuts. I pause my printer once it reaches to correct height during printing and then drop the nuts in. Then resume the print. Presto! Now you have nice grippy nuts to use. The grippers are just quality of life improvements and are of course optional.

I had these springs in my assortment and seem to be a nice amount of tension. Tension is important to keep the line tight. You could sub in elastic bands if you have those on hands. Just be advised that they dry out over time especially if you keep this tool in your tackle box.

When putting the line in the device, preload the springs a bit so it will pull the lines tight.  See picture with hand.

The smaller screw holes are sized to let a 6-32 self tap. You could use a tap to make threads or drill them out and use a nylon nut (or use thread locker and a regular nut). The point is, you can't have these screws tight otherwise the tool won't pivot right. 

I also used a few small metal washers between the layers so keep them moving free (pictured). 

Probably should print this is in something that can take high temps if you plan to use this in the summer.

I'm now back from my trip and this tool helped a lot. I hope it will help you too.