Quick question on white ash, trapped back or no?

[Mo_coon-catcher]

I'm making a reflex reflex for a guy in trade for a couple of muskrat mounts. My aim for it is about 55# @ 23" with 27" limbs and it will be heat treated. It's been a few years since I've used ash and can't remember, does white ash prefer a rectangular cross section or a trapped back? I'm thinking trapped but can't quite remember.

Thanks,
Kyle

[DavidV]

I've never used white ash for bows (doesn't grow much here) but by the numbers it looks to be a good candidate for trapping. I think Jim Davis does quite a bit of trapped ash pyramid bows.

[tattoo dave]

Do you mean reflex Deflex, or you really gonna reflex handle and tips? All the ash bows I've made were reflex tips and deflex bendy handle, with either a rectangular or d shaped cross section. They all worked out fine. I never have done a trapped back, so I can't really speak much of one. Anyway, post up some progress pics when ya get after it, and good luck with it.

Tattoo Dave

[Jim Davis]

Yes, I have  done a lot of ash with narrowed backs.  Mine were all "pyramid" design. I was pretty convinced that narrowing the back was the best approach, but time and more bows have mellowed my view.

Especially with the "pyramid" design, the grain runs off both edges of the tapered limb. I had several disappointing failures near the tips with the back ring lifting splinters at the edges. Now, I don't feel it is useful to strongly narrow the backs of bows.

The gain in narrowing, cutely called "trapping," is in reducing limb weight. (Balancing tension and compression strength turns out to be a pursuit whose value is uncertain, much as I liked the idea.) The tips are the area where weight reduction would most benefit performance, but they are also the area where the edges are most likely to lift splinters.

So, at this point, I am no longer confident that trapping is very useful, unless you are trying to catch a coon. 

Jim Davis