Started my new BBI!

[Apex Predator]

Here is my first bamboo backed/action boo/Ipe tri-lam.  I glued in 2 1/2" of reflex expecting it to relax more out of the form.  My BBI went from 2 1/2" reflex to only 1" out of the form.  This one retained 2" of reflex!  The action boo core tapers to 1/8", the boo backing is around 1/8", and the ipe tapers to about 3/16".  It looks like it will pull 100#!  I think I have quite a bit of wood removal, but want to retain ipe on the belly.  Some have said that the ipe can't get too thin or it will fail?  The blank measures 65" overall.  I laminated 6 thin pieces for the handle and have made the fadeouts about three inches long and thin instead of using a power lam.  Right now the tips are 1/2" wide, but I may have to make them narrower to keep some ipe on the belly.  I don't want to glue on my tip overlays until I'm a little closer to final profile.  I'm looking for 50@27.  Any ideas?

[adb]

Looks like there is no taper from grip to tips. I would start by tapering to about 3/8" nocks, before removing any belly wood. Nice work... should make a dandy.

[Apex Predator]

The bow is right at 7/8" at the fades tapering in width to 1/2" tips.  The tips are as deep as they are wide right now.

[adb]

Hey,
I'd still taper the tips a bit more. Will make the bow faster, and less hand shock.

[Apex Predator]

I just hated making them more narrow than they are deep.  Thought I may have stability issues?

[wytetale]

If it feels real heavy what I always do is draw a line down the belly of each limb about 1/4" wide and file it off on a 45deg angle.You can do the bamboo also. Then sand the edges over abit.

[Rich Saffold]

Looks like fun Marty , Remember if you get "any" wood to thin it will fail, Ipe being among, if not the last to do so..But I too would get the tips smaller since you will need a good taper both ways to maintain lateral stability. If you get it right, it will be beyond fast, if not you will have a kids bow...

I'd put overlays on and have the tip at 3/8th's square, well rounded is better, I would also angle the overlay so the back of the bow string loop is flush with the back of the bamboo or close..You are going to need everything working for you to keep stability, and that includes the straightness of the ipe..

This bow might end up more stable at a heavier weight since less wood removal, but you have a good 16" to remove off that belly before its going to move much anyhow. This is where floor tillering becomes very important so you can feel if its staying laterally stable..If you clamp this into a vice set-up and use a long string..you might have a limb twist off..

Rich

[Apex Predator]

This one might be done for.  I'll hold off pronouncing it dead just yet, but it's close.  I removed enough wood to get it bending evenly on a long string.  When I strung it up on a short brace length string she wanted to flip flop real bad.  Got the string on her and one limb is bending and twisted pretty bad and the other is very stiff.  I stopped right there, marked a hinge, and unstrung her.  The twisted limb almost lost all the reflex in one fell swoop!  I think this design was a little ambitious for my meager skills.  How to proceed? 

[radius]

On a laminated bow i made recently, my backstrip of hickory was very thick: 3/16 +...I wanted to keep the belly wood, like you do, so I tillered by taking material from the sides and the BACK.  But you have bamboo here and might not want to do that.  I have found that you can sand the nodes right down on bamboo, no trouble.  My BBO is 1 inch wide, and pulls 70# at 28". 

I don't know about you, but I like to make every bow I begin.  I want to finish it out at a workable bow.  Sometimes the weight is less than I would have liked.  If this BBI of yours were in my hands, I would facet it, like somebody already suggested, and take it safely to full draw.

[Rich Saffold]

Marty, you did bite off a big chunk with this bow, but switch out the action boo for real bamboo and its very close to a style I make. It is technically much more difficult to tiller, and what happened is exactly what I thought would..

If you were to shorten it and use side nocks it might be savable, You  most likely would have  succeeded if the limbs were 1 1/8" wide outside the grip when you got it bending so you had the proper taper and the  lateral stability that comes with it..

TB1111 has a pic of how I do these limbs in Tim Baker's chapter on performance..By trapping the back it allows the belly wood to have the most influence on lateral stability, but with two lams of bamboo retains a very low limb mass which is really the biggest reason to make a bow like this..

Rich

[Apex Predator]

This one died a horrible death folks!  Tried to work out the twist/hinge and ended up with no ipe left on the belly.  It went from 60# down to 20# in a hurry with no ipe left.  I cut the handle off and glued it to another core.  I will back with boo tonight.  Going back to a slight reflex glue up, and hoping for a straight profile hill type longbow.  I'll keep you all posted.