Thingiverse
Fletching Jig Arms
by Thingiverse
Last crawled date: 6 years, 1 month ago
There was a request for a "true helical" fletching arm for the jig as opposed to the offset that was included. I've wanted to see this myself for some time,so I attempted to make one.
There are two versions.
1-10 has the helix traversing 1/10th of the way around the arrow in the 53mm path. This translates to approximately a 2.4 degree offset at the base in rectangular coordinates.
1-8 has the helix traversing 1/8th of the way around the arrow in the 53mm path - more twist. This translates to approximately a 3.0 degree offset at the base of the vane.
1-8 V2 moves the vane up the arrow by 15mm, in case you have really long nocks or such.
I adjusted a few other aspects of the arm as well, but nothing that should prevent it from fitting on the existing base. It remains sized for the "standard" carbon arrow of approximately 0.3" OD.
Design aside, I don't actually think there is any point to this. If you apply a vane at an offset but then press the base flat against the arrow shaft, the base follows a helical path. I don't see gaps when using an offset arm, so it's fair to say that the base follows the arrow contour well enough. The fact that the jig arm didn't hold the non-glued edge of the very flexible vane in exactly the right place while gluing ends up being irrelevant... in theory. In reality, you can see the 1/8th helical vs. the equivalent offset and the vane does take a slightly different shape depending on the arm used.
Pictures of the arm are the 1/10th twist. Fletched arrows are with the 1/8th twist.
There are two versions.
1-10 has the helix traversing 1/10th of the way around the arrow in the 53mm path. This translates to approximately a 2.4 degree offset at the base in rectangular coordinates.
1-8 has the helix traversing 1/8th of the way around the arrow in the 53mm path - more twist. This translates to approximately a 3.0 degree offset at the base of the vane.
1-8 V2 moves the vane up the arrow by 15mm, in case you have really long nocks or such.
I adjusted a few other aspects of the arm as well, but nothing that should prevent it from fitting on the existing base. It remains sized for the "standard" carbon arrow of approximately 0.3" OD.
Design aside, I don't actually think there is any point to this. If you apply a vane at an offset but then press the base flat against the arrow shaft, the base follows a helical path. I don't see gaps when using an offset arm, so it's fair to say that the base follows the arrow contour well enough. The fact that the jig arm didn't hold the non-glued edge of the very flexible vane in exactly the right place while gluing ends up being irrelevant... in theory. In reality, you can see the 1/8th helical vs. the equivalent offset and the vane does take a slightly different shape depending on the arm used.
Pictures of the arm are the 1/10th twist. Fletched arrows are with the 1/8th twist.