Reflex tip selfbow

[Jackpine Boyz]

Hi,
Was wondering about a good resource for discussion on reflex designs and recurves for self bows. I do have the bowlers bible.  
I am most interested at this point in bow length changes when recurving and reflexing hickory or buckthorn selfbows.  I do have a 30" draw as well, so the stress to length becomes more of an issue as well.
Thanks

[Bob at Work]

email sent

[mikkekeswick]

Make them 66 inch long. Keep the radius tight and total limb length recurved short.

[Jackpine Boyz]

For my normal hickory selfbows I've been advised and having success with 68" ntn.  Recurves always seem shorter, but wouldn't the limbs be more stressed as I dropped from 68-66 and then recurved on top which I think adds even more stress?  Or is the initial recurve limbs actually returning to neutral stress then increasing stress once past the "neutral" position of a straight longbow.
I think I'm missing something in the physics of the limb strain.

[Pat B]

I've built R/D style bows from 47" long(sinew backed osage) to 60" sinew backed recurves and other recurves and reflexed and R/D bows to 66" for my 26" draw. Lots of it is choosing the right wood type and the specific stave for the project. If your tillering is good either style should work well for a 60" and up for a 28" draw and 62" to 64" would probably give you the best performance.

[BMorv]

I have made a total of 0 recurves, but have pondered this same question.  The answer is in bowyer's bible, I just can't remember the volume.  The part that you are missing is string angle.  The longer bow makes a better string to tip angle and prevents stacking.  With a recurve, you have a much better string angle so stacking is not an issue, so you can make it shorter.  A recurve is typically wider to accommodate for the shorter working limbs, and they normally take more set all else being equal.  This is why it takes a pretty good bowyer to pull one off (And hence why I haven't made one yet).   It helps if you pick a wood that can take heat treating to counteract the increased stress of a short working limb.  
I'll be following this closely as I want make a recurve as well, and I have a 29.5" draw.  Let us know how you proceed.