My first reflexed HBO (DANGER!!!)

[Pat B]

If across the limb there are a few options. What glue did you use?  From my experience the only time hickory breaks across the back is if rot had set in before it was milled. During warm weather it doesn't take a week for it to happen to wood tht is not properly cared for after cutting. Can you post pics?

[Balding Kansan]

I used TBIII. I don't think it would have had rot unless it was rotted from the supplier because it spent about week in a conditioned space then I glued it up where it spent the rest of it's time in a conditioned space.

[Pat B]

You can heat the backing and remove and replace it. TB glues will release at 150deg(F).
  It is very rare for hickory to break across the fibers. It will generally bend and possible splinter before ever breaking if it breaks at all. The only hickory I have seen break across the grain was on a HBO I made the backing from a hickory log that was given to me. It has been stored in a garage for 2 years and was quite dry. I had it cut mostly into backing strips with a few staves also. The first one I used broke across the grain. When I studied it I found discoloration and the wood had a powdery consistancy. Needles to say I had lots of expensive kindling that winter.
  I have made lots of hickory backed bows and some with backings that had such bad grain most folke would not use it for backings. I never had one like that break but one with some rot in it broke right off the bat.

[bigcountry]

speaking from experience, I would remove the backing, and add another.  I have put in enough effort in one bow to save it from problems, that I could have built another bow.  It was good experience, but looking back, I could have removed the boo and put another on in a jiffy compared to all the work I put in.

[Balding Kansan]

I guess i'll remove it. I just don't want to spend the $ to replace it for it to happen again. I do have a cache of sinew in the freezer. How would it compare to hickory? Increase/decrease draw weight?