Author Topic: First attempt build a long !  (Read 31095 times)

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Offline Stick Bender

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Re: Prepping horn ? and build a long !
« Reply #60 on: November 16, 2017, 09:16:16 am »
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mikekeswick

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Re: First attempt build a long !
« Reply #61 on: November 17, 2017, 01:50:59 am »
Don't do anymore narrowing. You may need the width later. Gluing the horn can induce twists. The thick and wide core acts like its own form.
You should get the core to the side profile you want. Glue the horn along a centreline. Then reduce the core.

Offline Stick Bender

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Re: First attempt build a long !
« Reply #62 on: November 17, 2017, 04:01:41 am »
Gotcha Mike makes sense especially  out on the outer  1/3  , thanks for stopping in doesn't seem to be a lot of interest on this side for composites !
If you fear failure you will never Try !

Offline Aaron H

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Re: First attempt build a long !
« Reply #63 on: November 17, 2017, 06:05:52 am »
Personally I think 62" is too long.  You are not taking advantage of the tension and compression properties of a horn and sinew composite.

Offline BowEd

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Re: First attempt build a long !
« Reply #64 on: November 17, 2017, 06:10:00 am »
Yes that's good advice from Mike and see his point.I was always able to get the exact proper thickness on the core before glueing the horn on all of mine and it worked fine too.Then applying the proper amount of sinew to get to the poundage I needed evenly and crowned nicely too with 3 applications of sinew within a 2 week span of time.Using Pat M's method of  shaping it and smoothing it after final application of sinew just with those 1" to 1.5" wide cotton strip wraps.Some light sanding will be required yet but it should end up nice and smooth and to the thickness taper you need.
BowEd
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Ed

Offline BowEd

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Re: First attempt build a long !
« Reply #65 on: November 17, 2017, 06:16:41 am »
Aaron...Ya I know what you mean there.He should only have sinew on 44 to 46 inches of the bow though including the 8" handle.He'll be drawing it to 30" I presume which the bow should handle that pretty easily yet too.
This all depends kinda on how much reflex Ritch induces into the bow.I know he's tentative about it but it's up to him.It's a first time type bow for him having not tillered a bow with a whole lot of reflex but 10 t 12 inches should be doable easily.
I've always used to had to C clamp the bow to the tlllering tree to tiller it but since I made that peg board which I guess he might it should'nt be a problem getting it to brace and then tillering on the tillering tree.
I'l let Ritch comment himself on his intentions.
« Last Edit: November 17, 2017, 06:44:35 am by BowEd »
BowEd
You got to stand for something or you'll fall for anything.
Ed

Offline Stick Bender

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Re: First attempt build a long !
« Reply #66 on: November 17, 2017, 07:05:43 am »
Aaron thanks for the comments  by most composite standards I agree but there is a couple caveats in this case , this bow is strickly a hunting type bow for legal reason I have to go to the field unstrung and string primitive type stringer in the blind or stand so thats a huge consideration , but by Eds reports with this design being similar should be able to get 180-190 Fps 500 grain arrow Im not looking for a rocket per say on this one just a very durable reliable hunting stable bow Im in the shop now and after Ed's and Mikes and what you said Arron  sugestions , Im shortening the working limb & TTT so no need for butt joint/length so far I figure 15 1/4 horn/limb 0.005 tapper core/limb & 57-60 TTT just trying to calculate draw weight with the mods still trying for 45-50 lb , Aaron this is my first composite & Im trying to take baby steps along the way but I dont want a dog ether once I get the system down I will make a more effecent composite !
If you fear failure you will never Try !

Offline Aaron H

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Re: First attempt build a long !
« Reply #67 on: November 17, 2017, 09:00:35 am »
It really is looking good so far Ritch.  Have you seen how the Koreans string their bows, sitting cross legged with no tools? With a light weight bow like your are aiming for, using this technique you should be able to string your bow in the field with a little practice.
I too am working on my first horn sinew composite right now, so I understand what you mean, crawl before your walk....

Offline Stick Bender

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Re: First attempt build a long !
« Reply #68 on: November 17, 2017, 11:40:17 am »
Also I plan on shooting heavy arrows 600-650 grain out of this bow so Im not looking at getting Eds numbers but here is the lay out with 62 TTT & 16 1/4  horn Im still leaning towards the longer 62 in. & butt jointing the exstention and I might prep some more horn and see if I can get some longer slats ,well see Im in no hurry just trying to get it right for what Im trying to do these bows are pretty work intensive for the time I have to put in so weighing my options !
If you fear failure you will never Try !

Offline Aaron H

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Re: First attempt build a long !
« Reply #69 on: November 17, 2017, 01:28:14 pm »
Your plan on using matching grooves, or no?

Offline Stick Bender

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Re: First attempt build a long !
« Reply #70 on: November 17, 2017, 02:27:07 pm »
Non matching how about you ? And Im using smooth on ,you ? I think Ed if I remember right didnt  use any groving at all with smooth on Im probably going to just ruff up the surfaces with 50 grit like the glass guys do , I think Adam mentioned in his book that matching grooves are a moderen addaption he never found any historical evedence for it , I think down the line I would like to try the magyar style like you, they seem to be Idealy suited for the WB horn , Hey Aaron did you end up getting yellow croaker bladders for glue ? Im using elk or moose sinew on this one I havent got around to making the bladder glue yet ! also are you tappering your horn ?
If you fear failure you will never Try !

Offline Aaron H

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Re: First attempt build a long !
« Reply #71 on: November 17, 2017, 03:06:30 pm »
Matching grooves, with fish bladder glue and rawhide glue.  You are correct, there is no evidence of matching grooves being used before 1930.
I ended up getting some sturgeon bladders from Bulgaria, I can give you a contact if you want it.  Croaker bladders would work probably just a well at half the cost of the sturgeon, but they say sturgeon is the best of the best when it comes to air bladder glue. I used it for peace of mind.
And yes, I tapered my horn from 5mm at the grip to 4.5mm at the base of the siyahs. 15" long horn, 48-49" ttt bow

Offline Stick Bender

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Re: First attempt build a long !
« Reply #72 on: November 17, 2017, 03:31:31 pm »
Ok I just remembered you where asking a while back on the yellow croaker bladders I'm just going to use that and high grade hide glue combo on the sinew I think if I were doing traditional glue up like you on the horn I would look to the sturgeon glue ,to that bow sounds nice ,what weight 65-70 lb there just guessing from your horn ? Look forward to you posting , I'm letting the sinew cure 16-18 weeks when I get there good luck there !
If you fear failure you will never Try !

Offline Aaron H

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Re: First attempt build a long !
« Reply #73 on: November 17, 2017, 05:37:48 pm »
Good guess, I'm hoping for anywhere from 50-70# if it makes it at all

mikekeswick

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Re: First attempt build a long !
« Reply #74 on: November 18, 2017, 02:30:22 am »
Any good quality glue is good enough. The main reason for using croaker glue is a longer 'open' time before gelling. Hide glue gels too fast for me but then it is never above 20 degs in my workshop, now I have a hard time getting it above 12 - 14 degs so the slower gelling glues are needed. Like I said don't worry about the strength of the bond with any collagen glue.
Bow length divided by 1.5 will give a drawlength. 62/1.5 = 41.3 inches.....:) I hear what you are saying about length/playing it safe etc honestly there is no need to play safe by under stressing the materials...they can take it and more. Sinew/wood/horn is a truly amazing combo after working with wood and all its limitations ;) You are highly unlikely to break a hornbow that is well made. Making it well made is the hard bit haha!
Put your sinew on in 1 mm thick layers, 2 weeks drying inbetween layers, sand with 80 grit inbetween layers and you can safely forgo the lengthy waiting times. I totally agree that if you put on thick layers you do need to wait  - thickness in mm squared - weeks. With the 1mm layers it really doesn't matter.
I would advise against wrapping a composites sinew layer, it is essential that there is enough glue in the matrix if not it could go bang...wrapping was not used on the old bows and they seem to be doing fine with beautiful aligned and flat sinew. It is all technique :) The Korean method of sinewing has a lot going for it. Excess weight is much better removed from the non bending sections.