New Questions!! -Osage bow design query (pics added)

[artcher1]

Decided to take a break from my meds!  How you guys been?

[Orangeman89]

Thanks Guys!!

 I was wondering what the advantage to the 8" parallel limb is out of the fades vs. a true pyramid.  I really don't know.  I was reading in TBB 4 that the "pyramid"  or the " Enhanced Andaman -Holmegaard" design were two of the better performing designs and just thought that I would try the pyramid first (easier tiller).  The information is under the chapter on Design and Performance Revisited.  There is a picture of two designs: "Enhanced Andaman-Holmegaard" and "Pyramid" on page 120. 

I have built four bows to completion so far.  All have been similar to the one suggested by artcher1, except they have all been between 66" and 68".   The parallel limbs have been anywhere from 4" from the fades to all the way to mid limb.  I really like them except they have all been around 1 3/8" or smaller in width out of the fades.  I have therefore ended up with bows between 42lbs. and 50lbs which is fine.  I just want to get around 55lbs.  The staves dictated that I go that thin.   

I guess my idea was to make a bow that was similar to the pyramid and the Holmegard.  My intent was to have the last 8" to 10" of outer limb be non-bending and this would in effect shorten up the working limb?  I sort of wanted something different than what I had been doing that followed the principals laid out in that chapter and also looked cool like the two bows pictured on page 120.  I added the slight deflex/reflex because I saw the Molly (lever-bow) bow that  Misslemaster showed here a month or so ago and thought that it was the cat's ass.  So I figured I would incorporate that into my design.  Plus it seems like that last few bows Blackhawk has displayed had the deflex/reflex profile as well.  I even thought that depending on what all of you folks came up with, I might end up sinew backing the working part of the limb and really making the non-working outter limb very thin and stiff. 

I am hoping you guys can help me design a monster that is really cool, shoots good, and might actually hold together  .  If it doesn't hold up, I have two more blanks that look just like the one pictured except they haven't been steamed and shaped.  Am I on the right track??
Thanks.  Mark

[RyanY]

Here are a couple osage bows that I made a couple years ago at MOJam and I think both designs would fit that stave nicely. The more narrow bow was super dense osage so it's quite narrow and heavy. I think the pyramid one is more what you're looking to do.
http://www.primitivearcher.com/smf/index.php/topic,27644.msg368851.html#msg368851

[artcher1]

Since Osage is better suited for a narrower design because of it's density/weight/elasticity, starting further out from the fades (like 8" or so) will give you more width at mid-limb for better lateral stability for a longer bow that you're wanting. Your problem, from what I see at this point, is that the reflex you steamed in isn't going to hold and you're left with a straight deflexed/string follow bow unless you heat treat that back in. So now you need to design you limbs around the deflexed handle for best performance.

Personally, I think 66-68" is too long for a R/D design. As I see it, the purpose of this design is to leverage the inner working limb and you can only make limbs so long before their physical weight becomes a factor (as in hand shock) in this design.

I noticed Baker didn't use Osage for his" Enhanced Andaman -Holmegaard" design. Hickory would be my choice also......Art B

[Orangeman89]

Artcher1,
Thank you for the response.  I am not opposed to going shorter, just haven't done it yet.  The form I have has about 3.25" of reflex in it.  The reflex didn't hold so well on the steamed wood, but the form did work great on taking out the propeller twist and straightening out the limbs.  My plan would be to use dry heat and cold clamp the bow just after I get the limbs bending abit.  On the last bow I built, I used the same form which gives about 3.25" of reflex.  After tillering and shooting a hundred arrows or so, and also leaving it strung for 3 hours at a time, it seems to be holding one inch of reflex when I hold it against a wall.  I am hoping that by getting the wood into the general deflex/reflex shape when green, it will be less stressful on the wood when I use dry heat to put full reflex into the limb and temper the belly abit.  The only reason I haven't tried something shorter is because I was worried about overstressing the limbs, and I also haven't had a blank that I could get more than 1/3/8 width out of.  Now that I have a few clean blanks with 2" inches, I am looking to get a little more radical in design.  From what I read, if any wood can handle lots of minipulation, it would be Osage (which is good cause that is all I have).  Again, I thank you for your insight and feel fortunate that I have folks like you to give advise and also play devil's advocate, etc.  I have been home sick the last few days, so I have really been struggling with cabin fever and this site has been a great relief in that respect.  Keep the opinions coming please.  I promise I will take pictures of what I end up with whether it be good or bad. 

Mark

[artcher1]

Mark, good Osage will easily handles higher weights even at 1 1/4" width. But fresh wood a little wider is prudent I think.

You'll need to crown/radius the belly of fresh wood more so that seasoned wood when heat treating to prevent cupping. Heat shrinkage is greater when using fresh wood I've noticed. Heat treating the outer limbs really well will make them lighter and more rigid also........Art B