Yew questions/design suggestions

[stuckinthemud]

 I have a yew stave, it was pipe straight, 57" long, 2" diameter, very few knots. When I split it, it split with a gentle heli twist of about 30° and sprang into 2 inches of deflex so, several courses of heat treatment will be needed.  Sapwood is 8mm (1/4") thick. At the handle the stave is 21 mm thick..  When I flexed the stave, the bark popped off.  I've never had that happen, I always take it off with drawknives and chase a ring. The top of the sapwood is a nice dark brown and I'd kinda like to keep it like that but is that the best idea, should I be reducing the sapwood for better performance? Also, is the bark popping off a bad sign concerning possible problems with the wood?



I guess as its so thin, a flatbow is the best design? or is hollow limb better on a high crown like this? Parallel sides or constant taper?

[Del the cat]

I'd suggest decrown just a nice strip down the back with a spokeshave... that will also give you a feel for if the sapwood is sound (nice and creamy texture) a very lightly curved belly will leave heartwood in the centre and sapwood showing down the sides. If the heartwood is wide enough you can narrow the sides to the point where you can just see the heart/sap boundary.
Take care not to decrown too much and risk exposing the heartwood...if required the decrowning can be continued round the entire back to give an even sapwood layer.It's a balancing act between removing all the heartwood or going through the sapwood. You can end up tillering by removing wood from belly, back and sides... other than that it's simple
Leaving it relatively wide gives a nice fast low stress style of bow. (see pic of back and belly)
Del

[stuckinthemud]

Starting to take a careful look as I lay out the tapers when I noticed the pith is doing something a bit weird. It started centrally but at the centre, its wandered right over to one edge of the heartwood. Is this going to cause me any difficulties?

[meanewood]

When this happens, I just use the center of the stave to measure out the profile of the bows width.

[bownarra]

Same here just use a measured 'center'. The bark popping off happens with a dried stave, don't worry. I wouldn't be touching it all. Just a light sanding to finish it. Sapwood at 1/4" thick is perfect.

[Del the cat]

Don't worry if the pith is a bit off to one side if it improves the layout of the bow (avoid it running right out of the side tho' !)
Look upon it as a guide line, more than a rigid centre line.
Nice to have it central at the grip if poss...
Del