Yew questions?

[Hawkdancer]

I moved my yew stave to the workbench!  Only looking for the right style, and trying to figure out how much sapwood to leave on!  I am leaning toward the Meare Heath style at about 40-45#.  Any and all advice is welcome!  Got to get my mojo working again!
Hawkdancer

[TimmyDeNorCal]

I think most responses will advise 1/8" to 1/4" of sapwood, with maybe most leaning toward 1/4".

This, of course, is barring any additional information that might preclude the ~1/4" or so advice (e.g., stave back irregularities; presence of troublesome knots; low density; heartwood issues, etc.).

I just finished my first yew self bow. I ended up leaving about 3/16" of sapwood, on average. I also backed the bow with some nice rawhide, the whiter kind that matched the yew sapwood better than some of the more tan & semi-translucent stuff. The bow stave had a few troublesome knots on the very edge of one limb, and a few punky holes I plugged. So far the bow is holding up great. And it's quick, too. 62" nock-to-nock; ~56# @ 26.5" or so.

[Aksel]

I wouldn´t´t thin sapwood unless it´s very thick, over half of the staves thickness in the grip. Primitive yew bows from the stone age to the iron age in Europe had sometimes only sapwood in the outer ends of the bows. I have also seen many report good performance for bows with low amount heart wood. So it seems thinning is more a question of aestethics. 

Should also add I am not an expert in making yew bows. Only made about 10 yew bows and have never bothered thinning the sapwood. They all hold low amount of set and shoot equal to my elm bows.

[superdav95]

I personally like the sapwood/heartwood ratio about 1:3.  This usually equates to around 1/8” sapwood.  This will depend on the length of you bow too and style and width of your limbs.  The longer the bow the thicker you could leave the sapwood if you get my drift.  The shorter the bow the less leverage and you may end up with 1/4” of sapwood and a sliver of heartwood if going for a 40-45lbs draw weight.  Hopefully this makes sense.  Making the limbs narrower too will change things as far as sapwood/heartwood ratio.  I’ve also seen some really good performers out of longbows with narrow limbs with 1:2 or 1:1 ratios. These bows are sometimes 1 1/2” or under in width at widest point then taper on out.  Typically for me if making a recurve style flat bow with yew I’d go with 1/8” on sapwood and still have a good balance of heartwood on 1 3/4” wide limbs at widest point out of the fades.  Hope this helps.