Primitive Archer

Main Discussion Area => Arrows => Topic started by: Scyth on February 24, 2019, 11:00:33 am

Title: Understanding Dynamic Arrow Spine
Post by: Scyth on February 24, 2019, 11:00:33 am

Understanding  Dynamic  Arrow Spine by Paul Fender

https://ohlonearchery.com/understanding-dynamic-arrow-spine-characteristics/

. . . I knew there was a good reason about building (the pain in “gluteus maximus”) double tapered arrow shaft . . .


regards,

Scyth

Title: Re: Understanding Dynamic Arrow Spine
Post by: DC on February 24, 2019, 11:47:52 am

Interesting Scyth, thanks for that :)

Title: Re: Understanding Dynamic Arrow Spine
Post by: TSA on February 25, 2019, 10:05:31 am

thanks for that!! :OK

Title: Re: Understanding Dynamic Arrow Spine
Post by: DC on February 25, 2019, 10:14:14 am

Makes you wonder if tapering in steps might set up even more waves and dampen even better.

Title: Re: Understanding Dynamic Arrow Spine
Post by: Scyth on February 25, 2019, 10:51:45 am

DC -

I’m looking for the references on the “ideal” locations of nodes on bamboo shafts : numbers of nodes, spacing along the shafts, etc.

. . . for same purposes as “tapering in steps” . . .

regards,

Scyth

Title: Re: Understanding Dynamic Arrow Spine
Post by: willie on February 27, 2019, 05:28:13 pm

interesting read

the physics presented about vibration and dampening seem right, but I don't know if his actual test method will yield pertinent results for arrow evaluation

 clamping the arrow at one end might be a different situation than an arrow in free flight that would flex at its "nodes"

see           

Code: [Select]

http://www.bow-international.com/features/technique/flex-in-free-flight/
when considering a single taper bamboo arrow, I wonder if you would consider the possibility of changing the weight distribution along the arrow to make it "tune" different? add external weights along the shaft for testing? and maybe add inject? internal weight on the finished models

coming up with a way to evaluate the vibes in a free flying shaft would be the challenge
also, if there is a rotation of the flexing arrow, vibrations can be affected and possibly dampened to an advantage?