Author Topic: Sinew & Bow length  (Read 5501 times)

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Offline DC

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Re: Sinew & Bow length
« Reply #15 on: May 06, 2018, 02:08:48 pm »
Too much reflex can be a little unstable, hard to brace, that stuff.

Offline bradsmith2010

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Re: Sinew & Bow length
« Reply #16 on: May 06, 2018, 02:10:17 pm »
one time I made a 80# sinew bow, it was a dog,, but at that weight the arrow shot pretty hard,,enough to kill anything,,

Offline Marc St Louis

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Re: Sinew & Bow length
« Reply #17 on: May 06, 2018, 02:10:46 pm »
I made this sinew backed BL bow in 2002.  The bow is 64" long, pulled about 80# @ 28", and had a fair amount of reflex, this means string tension was pretty high.  Generally I was building bows like this around 60" long for a 28" draw but went with 64" on this one.  It was a mistake.  I could see from shooting the bow that it was a dog.  The sinew backed recurves like this one that I made before shot much faster even with 10~15# less draw weight.  It would have been better at a longer draw

A couple pics of the bow

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Offline PatM

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Re: Sinew & Bow length
« Reply #18 on: May 06, 2018, 02:26:31 pm »
I remember that one. Where did it end up.? Probably would have came to life at 30 plus.

Offline willie

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Re: Sinew & Bow length
« Reply #19 on: May 06, 2018, 02:30:37 pm »
Isn't the idea of pulling in reflex more to allow the sinew/glue to shrink as much as possible rather than get more reflex. Maybe we should start with a deflexed bow so we get all the shrinkage but not as much reflex.

I dunno, I suppose the reflex or more bend to get to full draw is the reason these designs perform, its the sinew that allows the design to make the bend. If it could be done with an elastic materiel that was lighter or stiffer than sinew, then highly reflexed designs might do even better. Short of making the belly out of horn or hideglue with TP or such, I was just wondering how to get the best work without set from a wood belly,

Seems like Stick is looking to design for heavy arrows with out necessarily  going shorter? I am not conversant in Asiatic sinew bows, but weren't some more about launching heavy "warbow" arrows, while others were more about light arrows? What design principles differentiated these two types?

Maybe PatM has a pic of each type to share?

Offline Stick Bender

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Re: Sinew & Bow length
« Reply #20 on: May 06, 2018, 02:31:47 pm »
That's a beautiful bow Marc I also remember a 64 in. Maple/sinew bow you built for PA magazine a number of years back that was a good performer !
If you fear failure you will never Try !

Offline PatM

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Re: Sinew & Bow length
« Reply #21 on: May 06, 2018, 02:49:07 pm »
Manchu bows were designed for heavy arrows. Not surprisingly they are much longer with longer draws as well.

  Those style of bows transition down through the Crimean Tatar bows to regular Turkish bows and then short pure flight Turkish bows.

Offline willie

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Re: Sinew & Bow length
« Reply #22 on: May 06, 2018, 02:55:38 pm »
Well , he's got the longer draw, and seems to be ok with a longer bow.  What sets these manchu designs apart from the bows for lighter arrows?

sinew proportions? working limb length proportions?  etc.

Offline PatM

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Re: Sinew & Bow length
« Reply #23 on: May 06, 2018, 03:09:32 pm »
  Larger all around. Much longer Siyahs with  sharper angles.

Offline willie

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Re: Sinew & Bow length
« Reply #24 on: May 06, 2018, 03:27:23 pm »

Offline PatM

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Re: Sinew & Bow length
« Reply #25 on: May 06, 2018, 03:46:24 pm »
Just that wood and sinew had a lot more to offer than most assume. 

Offline willie

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Re: Sinew & Bow length
« Reply #26 on: May 06, 2018, 06:21:52 pm »
so that is a wood/sinew composite?  how thick is the sinew, what is the wood?

Offline PatM

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Re: Sinew & Bow length
« Reply #27 on: May 06, 2018, 06:43:42 pm »
Yes. I  don't really know how thick the sinew is.  I made it 17 years ago in a very short period of time.  A few months from cutting to finished product including sinewing it twice due to the commercial hide glue being bad. It's Elm.

 As an aside I'm puzzled how photobucket pics have survived the purge on that site.

Offline Marc St Louis

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Re: Sinew & Bow length
« Reply #28 on: May 06, 2018, 07:26:27 pm »
I remember that one. Where did it end up.? Probably would have came to life at 30 plus.

Still have it and yes it would have done well at a longer draw.  Way too much bow for me now

That's a beautiful bow Marc I also remember a 64 in. Maple/sinew bow you built for PA magazine a number of years back that was a good performer !

My memory fails me there.  I don't remember ever building a sinew backed Maple, it must have been some other wood.  I know I built a sinew backed bow for Steve Quinton that might have been 64" long, it was sinew backed HHB.  He has a 31" draw.
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Offline PatM

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Re: Sinew & Bow length
« Reply #29 on: May 06, 2018, 07:36:57 pm »
I remember that one. Where did it end up.? Probably would have came to life at 30 plus.

Still have it and yes it would have done well at a longer draw.  Way too much bow for me now

That's a beautiful bow Marc I also remember a 64 in. Maple/sinew bow you built for PA magazine a number of years back that was a good performer !

My memory fails me there.  I don't remember ever building a sinew backed Maple, it must have been some other wood.  I know I built a sinew backed bow for Steve Quinton that might have been 64" long, it was sinew backed HHB.  He has a 31" draw.

 Be neat to see you at least two hand it through a chrono at 30 or so.

 He's probably thinking of that Yellow Birch.