Friday, 19 February 2016

Yew Sapwood Mini Bow

I've been trimming all my Yew from Jan/Feb 2015, there are loads of long triangular section offcuts which I've mostly sawn up for firewood.
On Primitive Archer one of the guys suggested a contest to see who could get the most draw length/bow length for a 40# self bow. This got me to thinking that Yew sapwood is very supple and most of the offcuts are sapwood. Unfortunately most are triangular section from the edges of the logs and there's not enough wood for 40#, but I wanted to have a play anyhow.

I roughed out a quick bow about an inch wide and roughly tapered it on the bandsaw and a bit of spokeshave work.
A quick try on the tiller shows how supple it is. The tiller is off with a bit of a weak point mid limb on the right limb, with the left limb and grip being a tad stiff.
Still it may be instructive to post a bow with bad tiller to show how it looks, it's how we learn, and that's exactly what I'm doing here.
I've not played with a just sapwood bow, I may try heat treating it and I've already "flipped the tips"(putting in a sharp recurve). It's about seeing what draw length and weight I can get out of it, it's only taken about an hour or two, admittedly using the bandsaw, but it shows how quick and easy it can be to experiment. In putting the sharp recurve in one tip I managed to get a bit of a splinter lifting on the belly, but I just rasped and sanded it out and glued on a V thin slat of sapwood (about 1/8"). That's now curing over my bench light with a 100watt bulb in it.
By easing off the grip and the left limb, the hinge in the right will be less stressed, I can always heat treat that area, but I expect it will just even out as I improve the tiller.
I did my usual trick of leaving the bark on and it has popped off (except at the very tips) leaving a lovely clean back which has a yellowish tinge
I'm hoping for about 30# @27" from a 47.5" bow !
Despite that huge bend it has taken very little set.

The real point of this is to show that you can make a small 20# bow relatively quickly and easily... if you have some decent seasoned wood. To take it further to 30# and then maybe higher, that's when the extra time patience and experimentation comes in. So don't be too ambitious with a first bow if you want that quick hit of success, but don't be scared of tinkering and improving to find out what the wood will do.
This one may well explode before it reaches 27" draw, but hopefully I'll catch it on video if it does!

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