Primitive Archer
Main Discussion Area => Bows => Topic started by: upstatenybowyer on October 17, 2018, 05:46:06 pm
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This is my most recent hard-backed yew d/r. I'd like to know what you think of the tiller, but I'm also trying to figure out why this bow is shooting a bit slower than my last one.
My last one pulled 43# @ 27" and shot in the 170s w/ a 10gpp arrow.
This bow pulls 53# @ 27" and shoots in the 160s w/ a 10ggp arrow.
Similarities...
-Both bows have the same length of working limb.
Differences...
-This bow is wider and has hooks.
-The last one had gradual reflex (no hooks).
-The outer limbs are working more on this one.
-The last one kept more reflex, I think because I didn't let the outers work as much, so it took less set. Is that the reason?
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The last bow...
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This bow...
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Looking at the pics all together, I just modified the first post.
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It looks like the recurved one has a little less reflex, is that so?
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Yes, Don absolutely. Upon looking at the pics all together, I modified the first post. I'm wondering if the first one kept more reflex cause I didn't let the outers work as much?
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My recurved ones are faster I think but I've only done a couple of each. I made a slightly larger(width and length) copy of my fastest bow and it was slower than the original.
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If the second one took less set I would have guessed it would be faster. What about mass? How much do they weigh?
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Good question. I haven't checked yet, but I'm quite sure the second one has more mass. It's got a bit more handle and a tanned snake skin on the back. Hmmm...
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Just looking at how the string lays I'd bet that the first one has a higher initial draw weight. Are you set up to do F/D graphs?
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Yup. Work's been crazy, but as soon as I get a chance I'll do one for each bow.
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When I posted the first bow Badger suggested leaving the tiller as is. He said if I got the outers bending more I might get more set and loose speed. I think that's exactly what happened on the second bow.
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Yeah, and I thought they should bend more. keep that in mind when reading my comments ;D ;D
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Im liking your bows lately Jeff 👍🏻
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Though slower the 2nd one looks a lot cooler with the hooks :-)
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Outside of different pieces of wood react different, here's my thoughts:
-Design. The 1st one has retained more reflex and will have higher early draw weight as Don suggest.
-10 lbs difference in draw weight. I know you are using 10 gpp as the standard, but it's less stress on a particular design to have less draw weight. For instance, if you would have tried to get 50 lbs out of the 1st bow it likely would have taken more set and wouldn't be near as fast.
-Your second bow is actually producing almost 10% more energy than the 1st
-If on your 1st bow you left the outers stiff (non working) and the second one you let the outers bend, then how is the working length the same. If you can pull off a small working area and minimize set doing so, it's a recipe for a fast bow, assuming you don't have excess mass. Take a look at some of the flight bows.
Hopefully Steve can chime in on his mass estimation. I'm just starting to weigh my bows and there's a lot of assumptions you have to make when coming up with a goal weight for these r/d bows.
It may just be my eyes and the photo, but the area of transition from deflex to reflex on the 2nd bow looks thinner than the surrounding areas in the braced and un-braced photos. It looks ok at full draw so it may just be the pic, but that's an area that is easy to scrape too much on. Any set there as Steve mentioned on your 1st bow will rob your speed.
And lastly, 160's with 530 grain arrow at 53 lbs isn't bad at all!
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Ill say it again, you are making some nice bows .
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Thanks a bunch everyone for your replies. :)
Ben, as always, you make some very insightful observations. One thing I've been pondering that you touched on is with the first bow the outers are working, just not as much as in the second one. I guess that's why I suggested they have the same length of working limb. However, with the first bow the outers aren't working nearly as much and I was wondering if that's a good thing. I'm having the feeling that with this style, it's a fine line between the outers not working enough, and the outers working too much. I'll have to look closer at that transition area in the second one. You may be on to something there...
Thanks again everyone.
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maybe the hooks could be reduced in size a bit,,width,,,so not add any extra weight there,,,,I like Bayou Bens take as well