New design for me.

[PatM]

Laubin's book shows that in an Eskimo bow although no cable is illustrated.

[upstatenybowyer]

Sorry Arvin, I should have read your post more carefully. 

[Selfbowman]

Upstate no problem . I don't explain myself clearly anyway. Arvin

[Selfbowman]

New pic

[Selfbowman]

Well it took set from mid limb to fades. I got some mass off at a price. The bow weighs 19.5 oz with a 9" handle 67 " ntn, 46-27. I have  shot 4 arrows thru it but they seemed fast and smooth for sure no shock. Moister meter said 7% but my gut says its higher. The flattened v shape lightened the load but gave me set as Pat and others thought. It was too dark to crono or flight test so not sure about that yet. Arvin

[PatM]

Do you ever just trap the back?

[Selfbowman]

Pat I have tried D bellys, flat with trapped edges, real symmetrical flat limbs the same thicknesses. I have gone from 1-1/4 to 1-1/2 at fades to 1-1/2 to 1-1/4 at mid limbs , all tapering to 1/8 -1/4 at tips. I know every piece of wood is going to be a bit different. God planed it that way in us and the trees I think. But my goal is to find the perfect mass placement for as little set as possible as light as possible on the ends. Can't do the math but pretty sure there lies my answer to my quest. All from Osage and from 67-69 in length. Some with 10" handle . This one is thicker at the fades to thinner at the tips v shaped somewhat. The limbs are one continuos decrease in width. Which makes midlimb right at one inch in width. No I have not trapped the back. Other than rolling the edges say 1/4 " in or so. Arvin

[Bob W.]

Arvin, just curious how long ago was that stave cut?  To me it seems the older the better at least 2 years.

[Bob W.]

2 years or more with with osage and roughing it out along the way is even better!

[Selfbowman]

Bob 1-1/2to 2 years I would guess. It must have came out of a big tree. It was a belly split about 3to3-1/2 " across the back. Pretty flat , even rings  , no knots , very little propeller in it. Good stave. The kind you would like to know where to leave the mass and where to take it off.  Arvin

[Selfbowman]

Pat tell me about trapping the back and its benefits if there are any. Arvin

[mikekeswick]

It makes the back work harder because there is less wood doing the tension work. It is a technique best saved fro tension strong/compression weak woods. Like ash, red oak, hickory etc. I have never found an osage stave yet that would benefit from it. Osage is one of the 'best' woods because the tension/compression strengths are very well matched, it is also very elastic. Maybe if you had a dead flat backed stave it may help slightly to trap the back but really all you would need to do is radius the corners.

[Selfbowman]

Ok Mike I would say that we still don't go thru the growth ring on the back. Or violate it evenly thru out the length of the limb on the edges? Or use a sapling - high crown back? Is the trick to keep the tension - compression even thru out the limb width even though it gets thinner on the outter edges of limbs? I have wood that I can do all these with. Remember going for no set. The BB recommends flat backs for best tension and flat bellys on Osage. The problem is getting the extra mass off and where it should come off . I know off the ends if possible. Steve told me extra inner limb mass is not as important as on the ends . That makes perfect since to me. Finding that happy medium with no set is the secret I would say .  If I succeed with this it's only because one I am hard headed and determined to do something that's near impossible. Two cause I don't know any better. And three I have to much time on hand. I don't think it's the latter. Arvin

[Selfbowman]

Mike I have built some dead flat back bows and rolled the edges slightly. Two took hardly any set at all but the mass was still on the slightly heavy side. They had great  cast but come up short. Lol Arvin

[bushboy]

Arvin,not to discouraged, I believe that Simpson concave belly would reduce mass and keep the set to a minium.