Tapered Doug Fir

[fujimo]

i have an amazing video of an arrow in slomo. and when spined correctly- its evident that the parallel shaft doesnt  touch the bow riser at all after release- except maybe for the first 2 or 3" behind the point.
just from what i have seen, i cant say if it does or doesnt help clear the riser better.
it does help with foc for sure- but i agree with Hermon, that may not be the only reason as to why they fly so well.
over the years i have been through the gamut of thoughts, ideas and theories as to why the tapered shafts fly so well.
a lot of this has been speculation ( mine included ) until recently i read a great write up on a website.
tests have been done measuring the duration of oscillation of the shaft- ie what would contribute to the shaft continuing to flex back and forth as it goes through the throes of " archers paradox".
different materials and different profiles will oscillate for different periods of time- the more homogeneous  in profile and in material a shaft is- the longer it will oscillate.
 makes sense - nothing to really disrupt the waves travelling back and forth down the shaft.
but, if a shaft has a back taper- that transition from parallel to the constriction in diameter- seems to really screw up the wave  structure-, disrupts it and kills the oscillation quicker, and quite a lot quicker too.

for a long time i have believed( and probably am partly correct in the assumption) that the improvement in FOC, is what made the shafts more stable- quicker to recover, and more forgiving, but i see now it is a lot more technical than that, but i do believe that the foc still adds to the advantages of the overall arrows performance. Maybe just to a lesser degree.
 but it appears that this recovery from oscillation seems to be the significant factor to the tapered shafts recovering from the "Paradox" phenomenon quicker than any other shaft- yes even quicker than carbons!

anyway- just some interesting info i stumbled across

[TradBrewSC]

i have an amazing video of an arrow in slomo. and when spined correctly- its evident that the parallel shaft doesnt  touch the bow riser at all after release- except maybe for the first 2 or 3" behind the point.
just from what i have seen, i cant say if it does or doesnt help clear the riser better.
it does help with foc for sure- but i agree with Hermon, that may not be the only reason as to why they fly so well.
over the years i have been through the gamut of thoughts, ideas and theories as to why the tapered shafts fly so well.
a lot of this has been speculation ( mine included ) until recently i read a great write up on a website.
tests have been done measuring the duration of oscillation of the shaft- ie what would contribute to the shaft continuing to flex back and forth as it goes through the throes of " archers paradox".
different materials and different profiles will oscillate for different periods of time- the more homogeneous  in profile and in material a shaft is- the longer it will oscillate.
 makes sense - nothing to really disrupt the waves travelling back and forth down the shaft.
but, if a shaft has a back taper- that transition from parallel to the constriction in diameter- seems to really screw up the wave  structure-, disrupts it and kills the oscillation quicker, and quite a lot quicker too.

for a long time i have believed( and probably am partly correct in the assumption) that the improvement in FOC, is what made the shafts more stable- quicker to recover, and more forgiving, but i see now it is a lot more technical than that, but i do believe that the foc still adds to the advantages of the overall arrows performance.

anyway- just some interesting info i stumbled across

Very interesting and thank you for sharing!

[fujimo]

yer welcome
i didnt figure it out- i just learnt it