design question

[Wiggy]

I'm working on my first bow, and I'm a little confused about how the belly should be shaped. The bow is made from a dogwood sapling, so the back has come curve to it (it's not flat) and I was wondering if the belly should be flat, or rounded? Are there any rules of thumb about the advantages or disadvantages of a rounded belly versus a flat one?

[George Tsoukalas]

I'd leave it flat to cut down on set. For the same reason I'd leave the stave an inch longer than you normally would but this is your first. LOL. What's your draw length? Jawge

[Wiggy]

Draw length is 26 inches. Right now, the stave is about 68" long.

[Pat B]

Like George said...Flat!  With a rounded belly most of the compression stresses are down the center of the limb. With a flat belly these stresses are distributed across and along the entire working portion of the limb. Some woods can handle that(osage) but I don't think dogwood can handle too much. Safer to go flat.

[Dauntless]

Perfectly flat limbs are harder to get though.  It's ok if the belly is a little rounded, it'll even help you get a good even thickness taper.  Well rounded corners are necessary even with a flat belly.  They keep the edges from kinking.

A rounder belly will cause more set, which isn't a big deal.  Dogwood is pretty dense too so you shouldn't have much to worry about.

The belly can be round or flat, just make sure you have a good thickness taper.  No dips, no hills.