I am building a bow with an experienced bowyer but am looking to make some changes to his typical bow design. His design is based around a 64" bow and I was looking to build a 58". We don't know how to get there except by trial and error. Maybe there are too many variables to give a straight forward answer, sweep of the limb,length of riser, limb profile, ect.. Maybe there is a reference that someone could recommend. I would love the input, thanks.
-Paolo
Binghams has blueprints for a 58" t/d, that would be a good place to start. You could modify it some if you wanted.
You can take off from the riser or the limbs.. your choice, but need to do the calc's on the poundage. The shorter the bow the more poundage for the same lam thickness.
Are you making a take down or one Piece?
It's a take down. What are the calc's? Is there an equation?
not an equation, but go to binghams website and there is a thickness chart. They have one for 58".. it is pretty accurate. I always over shoot it because I can narrow up the limbs to obtain the desired weight.
When you call Binhams,ask for one of the tech guys.You can tell them the style your tring to come up with and they can do a good job of matching it up with your goal weight.You will most likly need to use a 15"-17" riser and match a limb up to it.My guess is that your partners using a 21" riser for his 64".You could use the same limb design but make the limbs for a 62" then mount them to a 17"riser.The weight diffrence in my 64" t/d to my 60" t/d is 10#.Same limb.21" riser to 17" riser.Hope this helps you guys some.Good luck.