Primitive Archer
Main Discussion Area => Bows => Topic started by: upstatenybowyer on February 26, 2017, 05:33:29 pm
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For all the bows I crank out, I have yet to make a really successful r/d bow, self or laminate. That being said, I'm pretty motivated to make one.
Currently I have a nice piece of osage balanced out in a r/d profile and floor tillered. It's 64" ntn. I kept the limbs relatively wide for osage, 1.5" all the way out to the last 7 inches, then tapering down. My question is, If I'm shooting for close to 60# will I absolutely need a sinew back if I want it to keep its profile? If so, how thick?
Thank you very kindly
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no, you won't need sinew...you can easily make that a 70# bow.
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You will loose some of the reflex but at 60# I think you will be great. I like the profile.
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Thanks guys. As long as it keeps enough reflex to remain slightly above the neutral plane I'll be happy. I just didn't want to really start tillering and have it loose it all.
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Thanks guys. As long as it keeps enough reflex to remain slightly above the neutral plane I'll be happy. I just didn't want to really start tillering and have it loose it all.
That was a bit confusing but I think I get what you mean. Usually, the neutral plane is used to coin a virtual line (or plane) within the limb cross-section where the strained limb is neither under tension, neither under compression. Here you mean that the nocks should still be just in front of the handle at rest, iow, keeping at least a bit of reflex, no?
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Thanks guys. As long as it keeps enough reflex to remain slightly above the neutral plane I'll be happy. I just didn't want to really start tillering and have it loose it all.
That was a bit confusing but I think I get what you mean. Usually, the neutral plane is used to coin a virtual line (or plane) within the limb cross-section where the strained limb is neither under tension, neither under compression. Here you mean that the nocks should still be just in front of the handle at rest, iow, keeping at least a bit of reflex, no?
Yes indeed. Thanks for clearing that up for me. I always thought of it as an imaginary line through a perfectly straight bow (no string follow or reflex). My bad.
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I'm building 2 D/R that are 62" long. I sinew backed them after taking them off the form 6 months ago. I tillered 1 yesterday to 60# at 25", I'm shooting for 60# at 28". It lost about half of its reflex.(http://i666.photobucket.com/albums/vv24/licenseddadad/Mobile%20Uploads/2017-02/IMG_20170226_160511_zpsh3w4m2jo.jpg) (http://s666.photobucket.com/user/licenseddadad/media/Mobile%20Uploads/2017-02/IMG_20170226_160511_zpsh3w4m2jo.jpg.html)Here it is in front of the other one that I havent started tillering yet. I hope It holds whats left.(http://i666.photobucket.com/albums/vv24/licenseddadad/Mobile%20Uploads/2017-02/IMG_20170226_161735_zps9tuq0dsn.jpg) (http://s666.photobucket.com/user/licenseddadad/media/Mobile%20Uploads/2017-02/IMG_20170226_161735_zps9tuq0dsn.jpg.html)
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Thanks for posting this Bob. I'm thinking a thin layer of sinew certainly couldn't hurt, and I don't mind waiting. How thick of a layer did you put down on the one that lost 1/2 the reflex?
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Jeff I put 2 full layers and another layer down the middle. The reason I waited so long because my Osage wasn't totally seasoned so I heat bent it and Sinewed it and let it cure while the wood seasoned.
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I put the same amount on both bows, I haven't started bending the back one yet. I floor tillered almost to brace height before stringing them.
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One layer of sinew wont hold anymore than no layers will. If you want to sinew the bow, then do the usual 3-4 layers and cut about 3-4" off your blank. The key to holding reflex in an RD is tillering it correctly. I see way too many RD bows with very stiff tips and mids, that just yanks all the reflex right out because the fades are getting hammered.
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One layer of sinew wont hold anymore than no layers will. If you want to sinew the bow, then do the usual 3-4 layers and cut about 3-4" off your blank. The key to holding reflex in an RD is tillering it correctly. I see way too many RD bows with very stiff tips and mids, that just yanks all the reflex right out because the fades are getting hammered.
Thanks Pearl. I was hoping you might chime in. So do you think if I really take my time and get the mids and outers working I need to add sinew in order to keep the profile?
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I personally think you would be wasting a lot of sinew and time. It will be fine the way it is. Look back at Ty's BBO he finished up a few weeks back. Your profiles are nearly the same. Your tiller should look very close to his. Nice and even.
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X2 what PD said. At 64" you don't need to sinew back it unless you want to. Tillering is the .key !
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I personally think you would be wasting a lot of sinew and time. It will be fine the way it is. Look back at Ty's BBO he finished up a few weeks back. Your profiles are nearly the same. Your tiller should look very close to his. Nice and even.
Trying to find Ty's BBO and having no luck. Anyone know how to find it?
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https://www.primitivearcher.com/smf/index.php/topic,58288.msg806766.html#msg806766
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Ah, yes. I didn't think it was this one cause I was looking for "BBO." Thanks bubby. :)
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Nice starting point Jeff.Looking good.All done with dry heat?
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Ah, yes. I didn't think it was this one cause I was looking for "BBO." Thanks bubby. :)
You see how is tiller is even and round right up to where his reflex starts, that's key to low set. I see too many RD bows that get tillered to match somebody elses RD bow, and not the actual bow they are tillering. The result is a "V" shape tiller and a lot of set. If you want that classic "v" shape, you need a lot of early reflex in the limbs.
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Got it. When I finally get around to tillering I'll have this thread and Ty's on hand for reference. This really helps PD, so thanks a bunch. Good luck with your current builds. :)
Ed, yup... all done with the dry heat. It's all tillering from here on out. Wish me luck!
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You see how is tiller is even and round right up to where his reflex starts, that's key to low set. I see too many RD bows that get tillered to match somebody elses RD bow, and not the actual bow they are tillering. The result is a "V" shape tiller and a lot of set. If you want that classic "v" shape, you need a lot of early reflex in the limbs.
Which is not fun at all to tiller :-[ Although, someday I'll have to give it another shot, as those hybrid longbows with the triangular full draw look neat.
I was going to say that the profile looked a lot like mine. If you don't mind, will you post progress pictures of how the tillering goes? Even if the style is a challenge for you, the work you've been sharing has been getting better and better and it would be nice to see how it goes for you. I'm sure you'll nail it!
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Thanks for the encouragement ty. I'll certainly post pics of the progress. It may be a little slower than you'd expect as I've got taps in my sugar maples, which means lots of evaporating in my spare time. This is probably a blessing actually cause it'll force me to take my time. :)
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Don't be scared, you got this!
The only thing even a little tricky here is that it's 64", which to me is on the short side. But, the starting profile is great, you have the width, and it's OSAGE for heck sakes. You don't need the sinew.
Adding to what Pearl said, a LITTLE bend close to the fades translates out to a lot of tip movement. Then a tad more bend in the middle 50%-ish of both limbs, but don't completely flatten it out. Finally stiffer toward the tips.
Good luck.
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Great input Springbuck. Thanks for reminding me about what Pearl said. Sounds like going slow and steady on the mids with plenty of exercise in between scrapings will be key.
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Good info Pearl . Logged in. Arvin
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Hi everyone. So I did some work on this bow today and I'd love your input, especially on the tiller. It's currently pulling 60# at 24" which means I've got 3 more inches to go to get to my target 27" draw length. If I can keep that 60# I'll be really happy.
It has lost a bit of it's reflex but the unbraced profile still looks pretty good. The braced pic is at about 6". My very accommodating wife took a progression of pics as I continued drawing the bow. The last one is at about 24".
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last 1
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Hey, good to see it!
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Looking good upstate . I thought the tips were a bit heavy but after second look at the reflex - deflex maybe not. Arvin
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That's looking good so far. Looks like it could work a little more near the fades? Cheers- Brendan
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That bow is sure coming along!
It's hard for me to say with selfbows... But to me, the inner limbs do look a bit stiff. Particularly the top limb from the fade until that dark spot, but the bottom limb looks like the inner 1/3 could be bending a hair more... But I'm still learning how to read bows, so take what I say with a grain of salt.
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Thanks a bunch Arvin, Brendan and ty. I'll definitely think about what you guys said and proceed slowly. :OK
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I think it looks very close. I wouldn't touch the last 12", or so. Knock the weight down and balance it out with the working part of the limb, that's just off the grip to mid limb or a bit farther. Should be a winner.
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Good thread.I could use pointers on these types of bows.To me your very close Jeff,but what do I know.
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Man, I really appreciate your input boys. Hope I don't go and screw up!
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Use a straight edge to find flat spots and you cant lose.
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I agree. On R/D bows you don't want to force the inner third to bend to much, but it needs to do its share, and a little goes a long way. I can't see much movement there between those three progressive draw pics, but just a HAIR more and it'll be money.
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and... So, pretty hard to see even with the lines, because paint is imprecise, and the pics have tiny variances, but that thin yellow line crosses your wrist right at the "snuffbox" in both pics. It should move JUST barely enough to see.
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Maybe see it here.
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last
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PD, will do!
SB, So if I'm understanding that yellow line should move back just a hair?