Author Topic: Pyramid vs everything else  (Read 2310 times)

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Offline High-Desert

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Re: Pyramid vs everything else
« Reply #45 on: November 07, 2017, 01:09:56 pm »
I'm definitely a woodworker, and I like the look of pyramid bows over parallel limb bows and prefer to make them. Based on collective experience of everyone here, one won't outperform the other if both are made with a proper tiller and to know that is made to its optimum performance, it would take more than just an eyeball. It could be I'm not good enough that I can't get the last 2 fps out of a given design.
Eric

Offline leonwood

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Re: Pyramid vs everything else
« Reply #46 on: November 07, 2017, 01:23:51 pm »
I'm with Pat here, just build a nice static and it will be better in all aspects 8) 8) 8) did I mention before that I like static recurves?  ::)
Maybe I just suck at building pyramids but my statics, rd's and my mollys are all faster then my pyramids. (Backed up by chrono results)
On the other hand, it all comes down to how well the bow is tillered and how you match the design to the wood. An overstressed "whateverdesign" wil never outperform a well tillered pyramid which is as narrow as the wood will allow without taking set.

Offline bradsmith2010

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Re: Pyramid vs everything else
« Reply #47 on: November 07, 2017, 01:28:21 pm »
how fast are they,, )F(

Offline PatM

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Re: Pyramid vs everything else
« Reply #48 on: November 07, 2017, 01:38:56 pm »
Steve what bow design holds the current broad head record? And is it closer to a pyramid design with flipped tips and some reflex? Arvin  )F(

 Back in the day Chet Stevenson used a heavy static recurve to toss a broadhead shaft some ridiculous distance over 300 yards.

Offline bradsmith2010

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Re: Pyramid vs everything else
« Reply #49 on: November 07, 2017, 01:42:58 pm »
arent all well designed bows as narrow as the wood will allow without taking set,, ??

Offline leonwood

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Re: Pyramid vs everything else
« Reply #50 on: November 07, 2017, 01:48:37 pm »
arent all well designed bows as narrow as the wood will allow without taking set,, ??

That was exactly my point ;D

Offline joachimM

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Re: Pyramid vs everything else
« Reply #51 on: November 07, 2017, 02:22:02 pm »
I think how well a pyramid design performs depends on how you define performance. If you only look at fps, then among straight-stave bows with no recurves or reflex, a pyramid is a superior design (in my opinion).

Performance, as in FPS? If so, at what arrow mass?

you could also look at bow efficiency, how much of the energy that entered the draw is actually (and potentially) translated to arrow speed.
See for example Kooi & Bergman 1997, who compared efficiency of different bow designs.
https://www.researchgate.net/publication/285362259_An_approach_to_the_study_of_ancient_archery_using_mathematical_modelling

But for flight shooting, efficiency doesn't matter, rather arrow speed with very light arrows (dry fire speed).
this is where static recurves can shine. At 10 gpp, however, they don't perform better than the best straight self bows. Since pyramids inherently optimize mass versus strain in the lower limbs, just like ELBs actually, they can have higher dry fire speed than other straight bow designs. But at high arrow masses, this difference hardly matters.

Look for example at the broadhead flight records: they hardly differ between selfbow, sinew-backed recurves (I assume these are the most likely simple composite) and complex composite recurves (sinew-wood-horn recurves).
http://www.usflightarchery.com/pdf/2017-Flight-Records-Broadhead.pdf

The difference is marked, however, when comparing regular flight archery
http://www.usflightarchery.com/pdf/2017-Flight-Records-Regular.pdf
Tillering is easy. Problems arise when a bowyer thinks he's right and the wood is wrong.

Offline bradsmith2010

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Re: Pyramid vs everything else
« Reply #52 on: November 07, 2017, 02:29:59 pm »
wow,, (-P 

Offline Selfbowman

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Re: Pyramid vs everything else
« Reply #53 on: November 07, 2017, 03:07:24 pm »
Well stated brad and jw! I never make same bow twice because of the nature of the material.

Bows are like kids. You wanna turn out the best you can with each, but they will all have varying qualities out of your total control. Best to enjoy each for what it is.

I like the bows are like kids . Well put! Arvin
Well I'll say!!  Osage is king!!

Offline Badger

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Re: Pyramid vs everything else
« Reply #54 on: November 07, 2017, 03:27:38 pm »
    Pat, Both the 50# broadhead records that I hold are with moderate r/d designs, maybe 1 1/2" reflex. The limb shapes are similar to pyramid but the first inside 8 or so inches is parallel. One of the unlimited broadhead records is held by an English long bow I built for a guy, about 90#, I think it went somewhere over 280 yards but easily has 300 or more in it. I predict 70# self bows will be hitting 300 yards in the broadhead. If not a self bow then at least a 70# simple composite.

   In all honesty I am not very impressed with my own broadhead records. I haven't seen any real aggressive designs show up and push us to go a little more extreme to compete. I think the 50# will be creeping up into the 250 yard range.



    I did recently have an extremely fast 35# bow with parallel limbs and gentle recurves. Hitting over 200 yards with a broadhead. 

Offline Selfbowman

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Re: Pyramid vs everything else
« Reply #55 on: November 07, 2017, 04:08:35 pm »
I somehow doubt a pyramid would out do a mollegebet it a controlled test would be almost impossible.i could be wrong though?

Bring one to the salt flats . From experience that separates the old men from the boys.   ;D
Arvin
Well I'll say!!  Osage is king!!

Offline Danzn Bar

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Re: Pyramid vs everything else
« Reply #56 on: November 07, 2017, 04:50:54 pm »
Wow....I'm enjoying the heck out of this thread.  One of these days I'm going to shoot a couple of bows I've made through a chrony or for distance.  this one sure has inspired me to give it a shot....
DBar
Integrity is doing the right thing when no one is looking

Offline Danzn Bar

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Re: Pyramid vs everything else
« Reply #57 on: November 07, 2017, 04:56:38 pm »
@ Badger and Selfbowman.....How important is arrow design when shooting distance?  from my research you need to be a "good" bowyer and a "great" arrowsmith to do good at the salt flats (distance).  appreciate any comments....
DBar
Integrity is doing the right thing when no one is looking

Offline Selfbowman

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Re: Pyramid vs everything else
« Reply #58 on: November 07, 2017, 05:16:53 pm »
Danza Bar  arrows are about 40 present as I found out. I went with a 500 gr. heavy foc . Bad mistake! It cost me probably 20 yds. My distances was 202 yds in 50# selfbow broadhead class. I was 40yrds short in the 50# selfbow flight class with some borrowed arrows.  I will be fixing that arrow error! Can't load pics tonight for some reason. Probably me! My bows vary in width but all are not a pyramid or  parallel limbs. They usually are about a1/4" narrower at mid limb verses the fade, then to about a1/4 " at tips. Arvin
Well I'll say!!  Osage is king!!

Offline PatM

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Re: Pyramid vs everything else
« Reply #59 on: November 07, 2017, 05:32:00 pm »
Danza Bar  arrows are about 40 present as I found out. I went with a 500 gr. heavy foc . Bad mistake! It cost me probably 20 yds. My distances was 202 yds in 50# selfbow broadhead class. I was 40yrds short in the 50# selfbow flight class with some borrowed arrows.  I will be fixing that arrow error! Can't load pics tonight for some reason. Probably me! My bows vary in width but all are not a pyramid or  parallel limbs. They usually are about a1/4" narrower at mid limb verses the fade, then to about a1/4 " at tips. Arvin

Why not experiment? I know you've shown pics of stacks of similar bows with very similar results. Why not shake it up?