heat treating belly laminations

[woody]

Would it be advisable to make belly laminations ultra dry/heat treated (ala Marc St.Louis) if you are constructing a laminated bow? Or is there concern if the belly (not the back) lamination is ultra dry?
Thanks

[Jesse]

I thought about doing that on a bbo. I would think on a backed bow where you have plenty of belly wood it shouldnt be much different than doing it on a selfbow. I might be cautious about trying it to a thinner belly lam on a multi lam bow.   Try it and let us know

[Pat B]

If you heat treat the belly lam before glue up it shouldn't be a problem. Once the lams are together it would be difficult trying to get the belly hot enough without degrading the glue. I think Urac can take more heat than the other common glues...but can it take that much?. As long as you give the belly lam time to rehydrate before stressing you should be OK, but that might not be a factor as far as compression goes. I don't know.  It is with tension. When you heat treat(temper) wood you dry it but also harden. You still have to rehydrate but the hardness remains. It has solidified the resins within the wood.
  James Parker(robustus) tempers the bamboo bellies for his bows before he glues the lams. If you watched him temper his boo you would be surprised just how "heat treated" they are.     Your local fire dept should be on stand by! 

[woody]

This idea has been on my mind for awhile after reading other's postings and articles about heat treating bellies.  I should try identical bow designs, one with a heat-treated belly lam, one with a low MC belly lam, and one with both heat-treating and low MC and see which one performs best...or blows up!

Thanks for the input. 

[Pat B]

Heat treating creates low M/C. That is why you allow it to rehydrate for a few days after heat treating. No matter how you seal your bow the M/C will equalize to the R/H of your area. Un-heat treated wood will absorb the moisture from the atmosphere and it will effect the performance. Heat treated wood will also absorb the moisture from the atmosphere but the solidification of the resins(from heat treating) should help it resist the compression stresses associated with belly wood.