Advantage of flat vs. round belly bow

[bigcountry]

What is the advantage of a round belly bow?  Any?  Most tell me they are always slower performance compared to flat no matter the design.   

I see people making yew round belly, and still can't figure out why?   

Is it only good for high compression woods like IPE?  Or backed?

[Pat B]

It all depends on the type of wood, the skill of the bowyer and the design used. A rounded belly concentrates the compression down the center of the belly and a flat belly distributes the stresses along the entire limb. Wood like osage perform well with a slightly rounded belly, at least for me. If I tried that with ash, hickory or maple they would probably fret.
 I have seen successful whitewood bows with rounded bellies and have made osage and ipe bows with flat bellies. I try to match the wood and design to my skill level.     Pat

[Kegan]

I've found it really helps make tillering, and tapering, easier. I usually use white woods with tempered bellies. I've had really strong bows that had flat bellies stand well tillered for a while, but due to poor tapering (an artificially flat belly on a naturally curved stave) they would later develeoped horrible frets to the point of popping pieces of wood out. The only way to have helped prevent such over stress would have been to widen the limbs, and wide, flat limbs are a bear to tiller. Due to poor tapering, a bow quickly became jsut a wall hanger.

I also have a theory that rounded/radiused bellies, that they aren't nearly as bad on slightly offest limbs. I had two flatbows with slightly offset limbs develope frets along the edges, even when slightly rounded off. I haven't had such problems with rounded bellies.

Helps with tapering, and so long as you aren't overstressing or too quickly tillerign them, they won't give you problems. I haven't had any problems with speed either.

[bigcountry]

It seems a wide range of opinions on the subjects on alot of very experienced bowyers. 

I have always been intrigued by the English style bows. And always wondered why they built this style if it was so bad. 

I found this old article by outdoor life or something like that from the 30's or 40's and it was basically saying if the indians knew how to properly make an american flat bow, then white men would have not taken the west.  I realize there were predijices then. 

So what I got out of some of your posts was you like rounded bellies sometime for ease of tiller and realiability?  Or some wood may be suited for it?

I have a yew stave a friend sent me with some wind shake damage about 1" below the sapwood.  Its not the finest piece of wood, but I don't see yew much on the east coast.  Actually never.  It has a deep sapwood ring like almost 3/4".  From what I read, this would make a better narrow rounded belly bow than a flatbow.   

[Pat B]

Yew is incredible bow wood in that it has a perfect tension strong backing in its sapwood and a compression strong heartwood in the belly. Yew likes a rounded belly from my limited experience and it can take a deep narrow "D" cross section profile also. Glen St Charles' "Billets to Bows" is a good reference for American style yew bows. The West Coast Native Americans made quite a few different  styles of bows and yew was a favorite wood.
   If your stave is a challenge, think out of the box! Don't design a bow to make with that stave...let the stave tell you what it wants to be. Look at Keenan's build along with the Lilac(?) bow. He listened to the staves wishes and came out with a real nice shooter. Dana's Sumac bow is another example.
   Yew is good bow wood that is easy to work...but it is fragile. It can't take too much abuse. The yew bow I posted a few weeks ago is a good example( ) of a yew bow from a challenging stave.        Pat

[Gordon]

I like a somewhat rounded belly because it is easier to tiller and looks good. But I will only do that with woods that can take the compression stress such as yew, osage, and certain tropical hardwoods. I've tried rounded bellies on whitewood but they always seem to fret on me.

[radius]

Listen to Gordon:  he is the Man.

[bigcountry]

I like a somewhat rounded belly because it is easier to tiller and looks good. But I will only do that with woods that can take the compression stress such as yew, osage, and certain tropical hardwoods. I've tried rounded bellies on whitewood but they always seem to fret on me.

When people say ease of tiller, is it because it might be easy to get one side of a flat bow thinner?  I figured it would be easier to tiller a flatbow, where you can rasp flat accross the belly.

I guess I am going to have to try one.   

I have a newborn boy now. 3.5months now.  And it seems time is such a premium these days.  I get 1/2 hour here and there to play on my bows.  I should have started this hobby in my 20's where I could afford to experiment.

[JackCrafty]

For me, a flatbow is easier to tiller, but the tips will sometimes twist out of alignment...and I'll have to straighten the limb(s) so that the string bisects the handle.  In my experience, with a rounded belly there isn't as much twisting....but it's harder for me to taper the limbs evenly.

[adb]

It's very difficult to make a truly flat limbed bow. Even a "Flat bow" will have a slightly radiused belly profile. As a general rule for me, I keep the white woods wider & flatter, and yew and osage rounder. I certainly have an easier time making a rounded belly profile. The trick is to keep the profile even. Remember, a rounded profile will concentrate the compression forces at it's peak.

[Badger]

I think a rounded belly is fine if you design the bow around it. A narrow deep cross section just needs to have more working limb. Either a longer bow or a bend through the handle bow. The less working limb I have the flatter I make them. I also prefer a gentle rounded belly on my flatbows. To me a rounded belly is similar to just trapping the belly,