Perry ?

[Living_waters]

Ok I have just read some in depth explanations by Dan perry on the concept of surface travel at glue joints and the storage energy at the glue line. From What I understood him saying was that a thicker single layer belly will have more surface travel thus more energy at the glue line. He also said that multi lam bellies lost some energy in each glue line. but Baker in TB111 says that a bilam belly the is forced into an extreme reflex at glue up and then adding the backing lam with less reflex stored more energy inside the bow, essentially making a bow inside of a bow.

OK I have two questions, before reading Perry's explanation, I had planned on doing a trilam and running my belly lams up my riser. But now I am unsure if a trilam is actually better or I would be defeating some of my purpose in building a Perry bow? (I want any bow I make to be stable for all conditions, hunting,target etc.but particularly looking for a lower weight bow that has the performance of a higher weight bow)

And 2. If I under stood Perry right a narrower bow with a thicker belly will perform better. If so and I was wanting a draw weight in the 50lb range (after last years shoulder surgery) does any one have any suggestions on a 29" draw boo hickory bow? (the bamboo I ordered with this in mind was 1 1/2" heat treated, but will need thinned a little.)

[**DONOTDELETE**]

I'm not a wood bowyer.I build glass bows... but I have been working with wood for 40 years, and the tri-lam will definitely store more energy.

 each piece of wood has opposing forces of tension and compression. 3 lamination's will always be stronger than two, and if the glue bond is done correctly it should add longevity to the bow as well.

[rainman]

What Kirk said.  I also don't believe that you will notice a performance difference between the 2 unless you are an experienced flight shooter.

[Living_waters]

This was my thought too But Dan explained that strength was not the same as stored energy. He said  a good visual of this is an I beam, the wider the span between the horizontal plane the greater the stored energy. A reflexed bridge beam is not made stronger by making it wider or adding more horizontal layers, it is made stronger by making it deeper (strength being preloaded between the back and the belly and the force absorbed in the center of the beam) He said that is what makes the Perry concept different than "just reflex".

"50 50 lam thickness would never be ideal because of the decreased surface travel at the glue joint. Just as 4 lams of 25% would lessen the surface travel at the glue joints" dan perry

If I am seeing this right you could uncurl 4 equal layered materials easier than you could 2 that are 1/4 bonded to 3/4. I think you are right that a multi layer is more stable, but as this is sinking in I see that there would be more opposing internal force in 2 layers of the same thickness. But this theory makes my second question more critical since there would be a limit to the materials limits.