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WTT3 bow photos and FD curves (images on page 3)

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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby Kenro » Fri May 08, 2009 3:34 pm

Hornseeker wrote:So.. .abow can store X amount of energy and shoot an arrow super fast, but "not" be as efficient as another that stores similar amount but shoots an arrow slightly slower? By a long shot?? Dont get it.

Ive never payed much attention to the rule of stored energy from a bow of ANY given design. just energy recovery. (ie, limbs moving forward)
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby jwillis » Fri May 08, 2009 4:03 pm

Kenro wrote:...I'll get you the force draw numbers from my hotrod and can replace the empty FDC chart thats up? If you want?

I can do that! I'm sure everyone will like seeing the FD curve. That will also give us the dynamic efficiency, which I think will be a significant number on your bow (your bow is not the curviest, but shoots the fastest. This tells me your bow is more efficient.) The pics tell the story. It doesn't require the FD info to see that, but it will surely help. :) Jim
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby Hornseeker » Fri May 08, 2009 4:08 pm

So... Dans bow is super fast... but not especially efficient...ranging on the least efficient of the bunch...83% efficient at 198!!! TJ's is 93% efficient at 198... If Dan can up his efficiency to 90%...where many of us are near... he would have a 205+ bow easy... maybe 210? My prob is... I dont know why his bow isn't efficient and if he can up it????

I know ALL efforts were taken to make this accurrate... but that 83% or even his 81% efficiency...shooting 195 and 198... that seems wild? What am I missing???

E
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby Hornseeker » Fri May 08, 2009 4:13 pm

I would sure be interested to see what Dan's bow pulled from 28-29 and 29-30... I mean... is it really possible that his bow pulled .3 pounds from 27-28??

I have way too much to learn about how to manipulate that draw cycle :evil: I just want to yell the F word.... :twisted:
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby jwillis » Fri May 08, 2009 4:26 pm

Hornseeker wrote:TJ... for me... Centaur's numbers aren't there... just draw weight and speed??... :roll:

Ernie, we opted not to pull the Centaur slowly on the tree because it was creaking like a SOB! We were too ascairt...lol! In fact, we decided not to test it at all until we got permission from the owner to pull it to full draw. Ken called him and got permission and all was well. It seems that it was just the takedown "hinge" creaking and sending the sound and vibration up the limbs. It was a two-piece takedown with the "hinge" takedown system in the handle. It sure sounded like it was 'bout to explode. Anyway, the pics are very nice clues on this bow. It really looks a lot like Dan. S's bow at full draw...lots of bend near the handle, which is interesting. That Centaur bow we tested is the REAL DEAL. It shot nice, too, and the handle felt good.

I would sure be interested to see what Dan's bow pulled from 28-29 and 29-30... I mean... is it really possible that his bow pulled .3 pounds from 27-28??

I have way too much to learn about how to manipulate that draw cycle :evil: I just want to yell the F word.... :twisted:


So... Dans bow is super fast... but not especially efficient...ranging on the least efficient of the bunch...83% efficient at 198!!! TJ's is 93% efficient at 198... If Dan can up his efficiency to 90%...where many of us are near... he would have a 205+ bow easy... maybe 210? My prob is... I dont know why his bow isn't efficient and if he can up it????

I know ALL efforts were taken to make this accurrate... but that 83% or even his 81% efficiency...shooting 195 and 198... that seems wild? What am I missing???

I'm with you 100% on this Ernie. I just don't understand. I seriously question the data on Dan's bow. I just hope that the PDF is correct so we were able to shoot the right arrow and not one that was too light in weight. We all know most FD curves increase directly or at an increasing rate in the last two inches, whereas the data on this bow increases at a decreasing rate...weird. Another weird thing is that some of the other bows had what looked like low draw weights in the last inch. Marc and Ken were pulling the bows on the tree. I wonder if they where they were pulling them...if possibly the last weight recorded was only 1/4" farther? Hopefully, Ken or Marc can come on here and help explain. I personally measured the marks on the tree to confirm that they were correctly marked for AMO. The measuring started at the low point of the grip and the last mark on the tree was at 26-1/4". That is 28" AMO, because AMO is 26-1/4" from the deepest point of the grip plus 1-3/4" for a "standard" riser. Ken had a metal collar on the pulling cable and a stop on the wall that prevented the bow from being overdrawn, so even if there were some reading errors through the draw, the PDF should definitely have been right for each bow. Jim
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby Kirkll » Fri May 08, 2009 4:47 pm

Wow! looks like the old carpenter took all the marbles on efficiency. :D :D . Very interesting... i must have be holding my mouth right when i put them together huh? Even the one piece Sasquatch hit 93% :shock: :shock: What are the odds of getting that lucky on 3 bows? ;)

Of course Ken will probably post a higher number now, ank kick sand in my face... :lol: :lol:

For a guy that isn't real big on charts, i'm liking the looks of this batch ok.... :D

Hey Ernie, when laying up the limbs on the A boo riser bow, i made a point of shifting the lams in my form a bit so they didn't match yours. These have slightly different geometry than your limbs. i also altered the wedge configuration considerably from the way you run your wedges.
BTW those were just black glass limbs .040/.033

How about i just send you the bow and let you play with it bro? You think your riser has a built in over draw? Wait till you zoom in on this one. :shock:
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby BK in TEXAS » Fri May 08, 2009 8:45 pm

jwillis wrote: I wonder if they where they were pulling them...if possibly the last weight recorded was only 1/4" farther? Hopefully, Ken or Marc can come on here and help explain. I personally measured the marks on the tree to confirm that they were correctly marked for AMO. The measuring started at the low point of the grip and the last mark on the tree was at 26-1/4". That is 28" AMO, because AMO is 26-1/4" from the deepest point of the grip plus 1-3/4" for a "standard" riser. Ken had a metal collar on the pulling cable and a stop on the wall that prevented the bow from being overdrawn, so even if there were some reading errors through the draw, the PDF should definitely have been right for each bow. Jim


I noticed that while watching you do mine. The way he had the tree marked, 25" was actually 26 3/4", 26" was actually 27 3/4" and the full draw number (with the stop-collar) was indeed only 1/4" further, 26 1/4" or 28" AMO

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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby grizz » Fri May 08, 2009 10:11 pm

All I can say is that you put a lot of work into these charts! Very interesting, I will continue my limb profile,deflexion,mass,taper,studies. "A bunch of Garage Ninnies my butt!" :ugeek:
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby badger5149 » Fri May 08, 2009 10:45 pm

Someone asked about my bending comment, when I say further out toward the tip I just mean away from the handle or riser, it might only mean 3". A good experiment would be to take the highest energy storing bow and the highest efficiency bow and have them shoot both very heavy arrows and then very light arrows. Dan bow would likely kick ass with 20 grains to the pound while Kirks bow would likley kick ass at 5 grains to the pound. Both of them are very fast at 10 grains but would possibly excel even more at the extremes. These photos and graphs drive home several hard facts not the least of which is that there is more than one way to skin a cat. Us natural material bowyers we go back and forth all the time between energy storage and efficiency. I settled in with the r/d bow several years ago for the same reasons you guys have. Dans bow is right up there with top recurves for storing energy and his efficiency is not shabby at all for his design. Should be some great discussion come from all of this. This is what it is all about in my book. Steve
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Re: WTT3 bow photos and FD curves (images on page 3 added May 9)

Postby Kirkll » Fri May 08, 2009 11:09 pm

You guys think i should run some IBO weight arrow through the shooting machine just to see what she'll do?

5gpp ....that would be dangerously close to dry firing that thing.....that would only be a 256 grain arrow :shock: :shock: :shock: i don't think i'd want to risk blowing up the limbs personally/
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