New RO Bow

[woody]

Hi Everyone,

I am continuing to experiment with Red Oak boards to better learn bow design hands-on, and I thought I would continue to share my progress.  As always critiques, thoughts, suggestions, ruminations, etc. are welcomed.

My latest:
   - The boards: 2, 48" billets "W" spliced (1"x2"x4' boards) fairly straight grained
   - 76" overall (75" nock-nock) w/ 10" stiff handle section
   - Front View: 1 1/2" @ fades tapering to 1 3/8" @ mid-limb tapering to 3/8" @ tips
   - 56# @ 28"
   - About 1" of set after 2 shooting sessions
   - Accents of Asian Walnut (scrap hardwood flooring from a job) and poplar (reverse riser to cover up the splice)   
   - 3 coats of Shellac

Most of the thickness taper is in the first half of the limb, allowing for light, narrow stiff tips.  The tiller was meant to take advantage of leverage; though perhaps the concept was taken a bit too far…the upper limb is showing some chrysaling near the fade. 
I pocked some holes around the biggest chrysal as suggested in one of the TBBs, and it seems to be working so far.

I really love to shoot this bow.  The length allows for a sweet draw, and the stiff handle section eliminates any hand-shock.   


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[adb]

Chrysalling means the wood has been over stressed in that area. Looking at your full draw pic, the bow is doing most of it's bending right at the fades. The tips and midlimbs are very stiff, and that is why the bow has chrysalled at the fades. Start over, and make another, but distribute the bending over the entire limb. 

[Dano]

Tiller is about taking advantage of all the limb especially with a wood that isn't real great in compression strength, you have plenty of length and draw wieght, I would get those outer limbs moving some more, and mabe take some pressure off that area that chrysaled. 10" is a lot for a handle also, most use around 8", 4" for the grip and 2" fades. My 2 cents for what it's worth.

[Shaun]

Your overlayed handle material look like it comes to an abrupt end causing a stress point there. I try to make the transition from working limb to static handle happen over some distance, even a half inch transition has much less stress than a single point. I like your bow and making bows is the only good way to learn to make bows. You are doing well, keep at it.

[GregB]

Like already said, you need to get more of the limbs bending instead of just one small area out of the fades doing most of the work. When a bow's limbs are stiff out 2/3 of their outter length, the section of the limbs that are bending are overstressed and struggling to whip the heavy unbending sections forward on release...this energy is not efficiently transferred to the arrow due to the excess outer limb weight. The section that is bending will take a lot of set and performance will suffer.

[OldBow]

Lots of good info here from experienced bow makers.

[woody]

Thanks everybody...will do!

[Eric Krewson]

Make a Gizmo for your next tillering job.

http://tradgang.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=033419