rounded belly

[Stick Bender]

 Stop eating the burgers to much poison effect 

[joachimM]

It's the economy, stupid.

No, really. The reasons yew longbows had a rounded belly, was out of economy. You can cut more staves out of a log this way. It's described in Bjurhager et al. 2013, Fig 5. https://sci-hub.cc/https://doi.org/10.1515/hf-2012-0151
Since yew can take that extra compression (especially in the juvenile wood at the center of a log), and since Yew was so prized that the Medieval English cut nearly all yew woods on the European mainland (at least where they could lay there hands upon), economical use of the wood was required.

The belly of ELBs is rounded despite the disadvantage it yields.

[Del the cat]

That diagram is ludicrous!
The bow shape is wrong, those bows would bend sideways!
That log would probably give 4 bows, 6 if you were lucky, assuming it's roughly to scale.
Del

[Dances with squirrels]

I suspect they probably drew it like that to allow for the handle wood on a slightly deepened non-bending handle section. Imagine those shapes as a cross section of the handles, not the limbs. But I agree, I've never gotten that many staves from a yew log. They always seem to have issues I have to work around, and I tend to play it a little safer when sawing them out, leaving more wood around each one to allow for various design options, and layout and alignment options later. I usually get a few good staves/billets wide enough for ELB's or the occasional 'flatbow', and try to plan my cuts to allow for slicing some heartwood slats to be backed... if possible. There's not much waste after I get finished picking the meat off a yew log, but I'm not going to cut them into nothing but skinny staves that only allow for ELB's just so I get one or two more.

I don't radius or round bow bellies to ration my wood. I do it because I like them that way, to me they feel and appear a bit more refined, curvy, maintain the bow's shape and 'flow' from one tip, through the handle and dips, to the other, are more impervious to scrapes, dings and their effects, and better facilitate the shaping and tillering process, in my mind anyway, especially in character bows. I honestly don't know how I could make some of these bows with a rectangular cross section, even if I wanted to. If my radiused belly flatbows are a few fps slower, I wouldn't know or care or change them.

[Jim Davis]

Linking discussion to a different can of worms, "pyramid" bows can have a grow ring on the belly run from the fade all the way to the tip, because the limbs are the same thickness from fade to tip. Another advantage of the design--all late wood on the surface where the work is done.

[PatM]

Linking discussion to a different can of worms, "pyramid" bows can have a grow ring on the belly run from the fade all the way to the tip, because the limbs are the same thickness from fade to tip. Another advantage of the design--all late wood on the surface where the work is done.

 True, but that means you have to commit to larger weight drops per growth ring.

[bradsmith2010]

also if you are just working with a draw knife, the rounded belly is good for that,, and someone skilled could probably make the whole bow with the knife and not even need to sand it,,,please dont challenge me to do it,, just saying,,

[PatM]

A drawknife also used to be used for tapering cedar shakes so it does a wide flat surface pretty well too.

[Jim Davis]

Linking discussion to a different can of worms, "pyramid" bows can have a grow ring on the belly run from the fade all the way to the tip, because the limbs are the same thickness from fade to tip. Another advantage of the design--all late wood on the surface where the work is done.

 True, but that means you have to commit to larger weight drops per growth ring.

Actually, no. Weight in the pyramid bow is regulated by width.

[gfugal]

I think it would be a fun challenge for you experienced bowyer's to see if you can make a bow with nothing but a draw knife. I mean after you made  close to a 100 or so what's it going to hurt right 

[mikekeswick]

I think it would be a fun challenge for you experienced bowyer's to see if you can make a bow with nothing but a draw knife. I mean after you made  close to a 100 or so what's it going to hurt right 

It isn't difficult. Very easy to be real accurate with a properly sharp drawknife. Square the spine and you have a scraper too.

[PatM]

Linking discussion to a different can of worms, "pyramid" bows can have a grow ring on the belly run from the fade all the way to the tip, because the limbs are the same thickness from fade to tip. Another advantage of the design--all late wood on the surface where the work is done.

 True, but that means you have to commit to larger weight drops per growth ring.

Actually, no. Weight in the pyramid bow is regulated by width.

 You still have to choose a thickness.

[sleek]

I think it would be a fun challenge for you experienced bowyer's to see if you can make a bow with nothing but a draw knife. I mean after you made  close to a 100 or so what's it going to hurt right 

  Oh thats easy!