Please explane

[enewman]

Saw a video of a twister knoc. It is spring loaded so when you shoot it mechanically spine shaft

So a guy demo with recurve. Shot bare shaft was knoc right. He said this means stiff took standard knoc out and put in this twister knoc that weights 28 gn. Arrow shot straight.

Then he shot two fletch and one bare standard knoc. In target from left to right bare shaft leaning knock right Right next was fletched then second fletch. Bare that is leaning crossed trough the two fletched

Then he put the heavy knoc and it was straight with the group.

How can he say it was stiff and then adding weight to the knoc correct the lean. It should have been stiffer.

Thanks

[speck1]

I am no expert but I believe adding weight makes the shaft weaker not stiffer.

[RickBarbee]

I am no expert but I believe adding weight makes the shaft weaker not stiffer.

^^^THIS^^^ when adding weight to the front.

If adding weight to the rear the opposite is true.

Actually, weight does not change the actual static spine of the shaft at all.
Only the dynamic spine is changed.

What the weight does to the dynamic spine is two things:

(1) At front load - Increases, or decreases the leverage of the applied force against the static spine.

(2) At rear load - Increases, or decreases the amount of applied force against the static spine.

Rick

[enewman]

It's a twister knoc. It's adding weight to the knoc end. It it making it stiffer. But that is not what they are saying thanks

[SwampRabbit]

You will need to post up the video so that we know what they are "saying."

I would assume, based on the physics, that the nock isn't correcting dynamic spine, but rather it is adding angular torque to the shaft to create spin, much like fletching does, in order to dampen/correct the affects of weak/stiff spine, once the shaft reaches the target.

That would be my initial guess, need to see the video.

[enewman]

You will need to post up the video so that we know what they are "saying."

I would assume, based on the physics, that the nock isn't correcting dynamic spine, but rather it is adding angular torque to the shaft to create spin, much like fletching does, in order to dampen/correct the affects of weak/stiff spine, once the shaft reaches the target.

That would be my initial guess, need to see the video.

I tried. I'm Not smart enough to post video

[catslayer]

I tried. I'm Not smart enough to post video

Just post link we can make it work...

[enewman]

https://www.facebook.com/TwisterNock-778322535544862/videos

This Is what he sent me
It's the first video I'm talking about. The guy is shooting into a yellow target.
Thanks

[speck1]

This stuff is complicated! I fix teeth for a living. I feel like I need a physics degree to figure out how to get my arrows to fly straight. How in the heck did the Indians figure out what spine and weight they needed to kill buffalo? Now I am gonna have to search twister nock.

[RickBarbee]

These twister nocks are doing three things:

(1) They impart a significant spin to the arrow immediately upon exit of the string.

(2) Due to their additional weight, they are increasing load at the string, thus decreasing string speed, thus lessening the energy applied to the arrow, which causes it to react dynamically stiffer.

(3) Due to the immediate spin, the energy of the force & leverage have less effect on initial flexing of the shaft, and brings the effect of the fletching into play much quicker to maintain that spin. This allows the arrow to be in cleaner (no oscillation) flight much quicker than with standard nocks.

The concept actually does work, and works quite well. The only problem with it is - Most stickbow shooters tune for & rely on that initial flex of the shaft to give them fletching clearance. Eliminate the flex, and fletching contact issues may well follow, especially if shooting from the shelf.

Rick

[Bisch]

This is just a guess, but I'm thinking that the nock is imparting enough spin on the shaft to influence how it hits. So, the nock is in effect, acting like fletching.

Looks waaaaaay to gimicky to me. I'll stick with old fashioned tuning.

Bisch

[enewman]

I got what your saying Rick and thank you. What through me off was the guy in the Video said his arrow was stiff then he added more weight to the knoc end and it straighten right out. For me I would have thought for that to work the arrow would have been weak.

I understand arrows. I understand compound bows. I'm lost when it comes to traditional.

Thanks again

[Bisch]

This stuff is complicated! I fix teeth for a living. I feel like I need a physics degree to figure out how to get my arrows to fly straight. How in the heck did the Indians figure out what spine and weight they needed to kill buffalo? Now I am gonna have to search twister nock.

I would be willing to bet the indians made arrows, and kept the ones that flew good, and ditched the ones that did not fly well. After a while, they probably learned things that guided them to making more good arrows than bad ones.

Bisch

[RickBarbee]

What through me off was the guy in the Video said his arrow was stiff then he added more weight to the knoc end and it straighten right out.

You're right to me thrown by that, because he is mistaken about it. Adding the weight at the tail made his arrow dynamically stiffer. Creating immediate spin also makes the arrow behave dynamically stiffer.

I used turbonocks for a while. I could shoot arrows that were way to weak in spine, because the immediate spin corrected the excess flex.

Bisch, you are correct. The nock does the same thing as helical or offset fletching, except it gets the whole action happening instantly, instead have having to wait on the drag of the fletching to do it. This is why you can significantly reduce the size of the fletching when using these type nocks.

Rick

[SwampRabbit]

Yep, Rick pretty much explained what I figured was going on based on your description. The guy in the video mispeaks as to the reason for the change in flight.

I wouldn't use them personally. I don't like having to rely on lots of little things to work with the equipment to get proper flight. I'd just assume use a basic nock. Does it work? certainly... but does it work reliably? well maybe more reliable than my release

enewman... you really need to start shooting trad. I love messing with you on your tuning threads when you say things like "there is no such thing as too stiff an arrow." Come on over to the fun side!!! Where there are so many other things about arrow flight you never thought to think of.