I just could'nt resist throwing my two cents worth in. I have read about 7 pages of the earlier part of this discussion and decided I would comment.
I'm not near smart enough to even consider the issues on a physics level. Or maybe I should say
I'm too lazy mentally to try and apply myself to that understanding. I do however really appreciate the minds that some of you guys have and the way you are wired. It seems some people don't have to do the mental gymnastics to grasp these concepts and it comes with more ease. I have however benefited from considering the concepts presented regarding design, mass etc... Having considered these things I have drawn a few conclussions that I am confortable with to use as a basis for how I do my bows.
I think that Steve "Badger"s mass theory has merit in terms of optimizing effeciency when the mass is properly distributed throughout the bow. I like to make a bow that is not overbuilt but also not on the edge of destruction either. I don't need to make it the fastest bow around. I need to make it fast enough, without sacrificing durablity. I personally prefer bows around 60" long that will pull around 50# at my 26.5" draw length. I like to make my limbs moderatly narrow in the last 1/3 so as to gain as much cast as I can without sacrificing stability. I prefer to shoot a little heavier arrow (10gr per pound or a little more), so as to harvest as much of the energy stored in the limbs and therefore get good penetration and less of a bump on release. I like to have a bow that is light in the hand, balances well and draws smooth with little or no stack. I want it to be a pleasant expreience everytime I shoot it. For the most part thats what I am able to achieve these days.
Osage orange is what I have the most to work with and so I am very fond of it. I am fully convinced that it has the greatest combination of attributes that are conducive to making a bow such as I described above, time in and time out. I have tried to make good bows with hickory but over time they get sluggish due to the humidity. I have recently worked with Hackberry and find it pretty agreeable but I think I like the way osage recieves and retains its shape when trying to make heat correction in it. I am not impressed with red oak but I have only tried a couple. Mulberry is pretty good but the few I have done with it were not as dense as I would like I think I will try it again soon. My opinion is you can make a bow out of many different kinds of woods but for me, osage orange is just darn hard to beat. It does well in tension, compression, takes heat corrections with ease, is durable unlike so many others, does not get sluggish in high humidity, can get thrown around in the back of the truck and get a few nicks here and there and still be a sound bow. For me, If I was gonna make a bow that I needed to last me for the rest of my life and not worry about it in any condition, it will be osage.
I know I am biased and that I really have'nt tried a lot of different kinds of woods, but I don't need to, cuz I'm in love with the yellar wood and have plenty of it.
It is also excellent for heating and cooking, although my favorite combination for grilling over the open fire is a base of osage coals and then throw in a few semi green mulberry logs and you have a heat and flavor combination that is imparted to the meat that you can't beat at even the most high dollar restaraunts. We eat like kings around our campfires I can assure you.
So there is my two cents worth. Danny