Author Topic: Bow length:draw length theory  (Read 1448 times)

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Offline stuckinthemud

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Bow length:draw length theory
« on: April 12, 2021, 04:05:10 pm »
Let's say you draw 24 inches and have two 24 inch billets.  Assume good quality bow wood.  They could be spliced as 2, 3 or 5 piece. Deflex at handle, D/R, R/D and more besides.  Every splice loses a few inches off the bending section, so is the best way of making draw length a 3 piece spliced to give a slight deflex and reflex the outer thirds a little? Or some form of 5 piece? How would you approach this? This would be a 3-D or target bow.
« Last Edit: April 12, 2021, 04:18:41 pm by stuckinthemud »

Offline Del the cat

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Re: Bow length:draw length theory
« Reply #1 on: April 12, 2021, 04:32:21 pm »
short splices, back it with a continuous strip and make what you like.
Del
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Offline RyanY

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Re: Bow length:draw length theory
« Reply #2 on: April 12, 2021, 08:10:49 pm »
Some people will splice tips onto the ends. I recall a mollegabet style bow where the stiff outer limbs were Purple Heart. So you could do a bow in that style with a splice in the handle and then splices to add the length to the outer limbs. I wouldn’t feel comfortable bending splices unless they were very clean and backed.

bownarra

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Re: Bow length:draw length theory
« Reply #3 on: April 13, 2021, 03:00:07 am »
What Ryan said :) That would be my choice if you don't have  backing. Works well, I've also spliced on naturally grown recurves to a too short stave.
Splices under compression will eventually fail. If you make it like a hornbow you can do what you want BUT that would require two bellies and a backing....it would end up being pointless.

Offline stuckinthemud

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Re: Bow length:draw length theory
« Reply #4 on: April 13, 2021, 01:49:09 pm »
I have used splices bound with linen thread soaked in cyano.  Looked great and very strong.  My maths goes something like this: if I make a 3 piece, the handle splices will cost me between 8 and  6 inches of working length.  If I use a 12 inch handle my net gain in bow length is 4 to 6 inches which gives me draw length plus 10%.  If I splice in hooks/levers, I gain even more bow length but lose more working limb, so I could shorten the handle to 8 inches, or glue in an inch or two reflex but at what point does stress on the limbs get too high?
« Last Edit: April 13, 2021, 02:24:31 pm by stuckinthemud »