5 piece folding bamboo bows

[superdav95]

Here’s a few pics of the steamed revived limbs.   They are heat treated now will be set up like my other deflex out the handle style with gentle reflex mid limb but now incorporating the recurves. 

I estimate these limbs will make about 40-45lbs bow. 

[mmattockx]

there were some test results published a few years back that indicated with certian species of Banboo, the core materiel (belly side) had compression qualities that overpowered the outside (back side) in bend tests.

I don't suppose you recall where to find these test results? That would be interesting reading for those of us looking for good belly wood to use in lam bows.


Mark

[willie]

Hi Mark,
As I recall, the tests were published by a bamboo trade group and discussed breifly on paleoplanet about ten years ago.

While searching paleoplanet just now, I came across this interesting comment attributed to Tim Baker.  re:outer surface as belly

Takes more set per mass than any hardwood. It can be tempered with heat and gain in compression strength and elasticity. Fly rod makers do this, and bowmakers in the past also. Howard Hill for one. Untempered bamboo works well as belly wood if Perry reflexed. If making a bamboo selfbow its helpful to let the outer surface serve as belly, to prevent extreme set. The back is then composed of weaker inner fibers, but is more than strong enough. Yes, tiller on the back..

[willie]

here is some test data from the organization that most likely published the study I remembered
an example for one species......

This intensive investigation, although confined to a new world bamboo species viz :
Guadua angustifolia from Costa Rica in respect to just one important property, i.e., bending
strength
https://www.inbar.int/wp-content/uploads/2020/05/1489473435.pdf

6469 other resources are available for download at https://www.inbar.int/resources/search/?resource-type=all&keyword=

[mmattockx]

here is some test data from the organization that most likely published the study I remembered
an example for one species......

Thank you, sir.


Mark

[sleek]

Here’s a few pics of the steamed revived limbs.   They are heat treated now will be set up like my other deflex out the handle style with gentle reflex mid limb but now incorporating the recurves. 

I estimate these limbs will make about 40-45lbs bow. 

Those look fantastic. If you can figure a way to make these work your bows may take my record. Do you think you can keep the recurves stiff or will they want to open at full draw?

[superdav95]

Ok so I put a handle on these limbs and balanced them and only got 29-30 lbs draw.  Oh well they still worked very well and I would say test was successful.  The tip remained set and I suspect they are only slightly working tips.  They seem to be holding.  I put about 60 shots through it today and it shoots fine.  It’s light in the hand and no shock.  Very quiet and snappy for only 30lbs.  I’ll make the next one with thicker limbs now that I know it’s gonna work.   Either way good test.  Enjoy this little video clip showing me shoot it a bit.  Also included is a new 5 piece build folding version that is about 48lbs at 29”. 



https://youtu.be/wgHSxLW00c0?si=EoIPknzAwt-7R85E

[sleek]

What draw length did you get? Can you chrono it with a 300 grain arrow?

Yes, definitely a successful test! Looking forward to seeing future ones