boo-maple-ipé bow I'm working on, a reminder, and some questions

[dutchwarbow]

I've been working on this one, gotto fix a 'little' problem, and needs a finsish.

Current stats:
80#@28"
62" ntn
pyramidal frontprofile, glued up in R/D

My first trilam ever I had glued up. Choose for a 7mm maple core, and based it on a similar bow, but without r/d, and with 2 lams instead of 3. Made a measuring error, and the bow ended up too stiff. This core was a little too thick, and the reason for the compression fracture in the lower midlimb, as I had to sand of most of the ipé.

Not as bad as in the other bow, with a 3mm core. This was a Hybrid, with quite a bit of reflex, and 58" tall. I had to sand so much of the originally 2 ipé lams off, that I ended up with one, paperthin lam at the belly, wich got huge compression fractures;

please don't make the same mistakes as I did, and don't start with a lightweight core if you make a trilam from an unknown design. Who would have thought that a 3mm (1/8") core would have been too thick?

Okay,
now I have one other blank with a likely too thick core. Glued together with titebond. Any idea how to delaminate it properly, without hurting the wood? will heat work? might start a new topic on this.

I'm thinking about filling the little crysal with superglue, then finish the bow. What do you guys think?


 

 

(lower bow is the surviving one)
 

compression fracture in the lower limb of the 'surviver'
 

yeah, the ipé was real thin..
 

and it was even worse on the quadlam-who-became-a ipé veneer bellied boo backed maple

 

Nick

[Steve Kendrot]

Nick,

I wonder if it is not your lams that are too thick, but your Bamboo...? Everything I have read has instructed thinning the bamboo to as little as 1/16 or even thinner at the tips, and about an 1/8" at the handle. Your bamboo looks to be nearly an 1/8" at the tips (if your center core is 1/8"). My understanding is that bamboo is so strong in tension that it can overpower belly woods, and therefore must be thinned greatly to prevent crysaling and taking set. It seems to me its main function as a backing is to prevent splinters from lifting in the lams, not to add power to the bow necessarily. Maybe someone with more experience than me will chime in here.

Steve