Friday, 19 June 2015

Spliced Yew Bending Nicely

I spent a good deal of time yesterday going of the limbs evening up the thickness taper adjusting the line of the lower tip to try and stop the tendency to waggle and cleaning up the back.
There is one bit on the back where I go through several rings of the sapwood, the back has a sort of ripple in it a bit like the twist on a big rope. (see pic) And I've had to reduce the sapwood in places to ensure there is some heartwood on the belly and to try and keep the cross section of the bow relatively even/symmetrical. These things are all a compromise.

I'd been flexing it in my hand and was a bit anxious that if the splice did give out it could rip into my hand where I have a cut healing, so, as a safety measure I put a few layers of PVC tape over there just to contain any splinters if it did go.

I'm much more confident now it's coming back to about 27" at 60# That gives me some room to get the tips moving some more and to tweak the tiller.

The tiller shape has to reflect the unbraced shape of the bow, and in the full draw shot it makes like the tiller is a bit "square".
This bow is a perfect illustration of that, I'll explain:-
The tips (especially the left) will always look a bit stiff where it has a nice reflex curve unbraced.
It also looks stiff either side of the grip (especially the right), but there is a reflex or back set section just there (e.g the limb sweeps upwards a tad)
The deflex dip in the middle of each limb also contributes to the square look.

The right limb does need to move more in the outer 1/3 but that will happen as I narrow the limb a bit especially towards the tip when I fit the nocks.

I've just popped out and taken a pic of it unstrung so you can see what I'm talking about.
It's still got some reflex... which is nice.
All in all I'm very pleased. more work on it today and an update tomorrow.
video

In answer to the question asked below, here's a pic showing how I've marked the tip ready to shape it to add the horn nock. You can see the centreline has shifted from the original position (where the notch is cut in the end... that's where I guided a string to act as a line).
It's a small shift, but it all helps maintain alignment.

Oh F.F.S !....Just contrived to chop into the index finger of my left hand. Trying to get the axe to start a split along the grain on a tiny off cut to make a peg for a small hole near the nock on the lower limb. I was only tapping it and it slipped. At least it didn't take it off... must stay away from any sharp tools for a while. Not amused, F'ing and blinding..,.full of adrenalin...bugger.
And it smarts...
Never mind, let's have a nice cup of tea.
On the plus side, at least I've got the Steri-strips !

A couple of hours later, the cut has closed nicely. It looks as though the edge of the fingernail stopped it going too deep so it's more of a slice. Hopefully it will mend pretty quick, the last one has healed nicely.
I was really annoyed with myself, a mixture of impatience stupidity and complacency.
On the plus side, I'm being let off cooking duty tonight.

4 comments:

  1. Could you explain "waggle" please. I understand the word, just not how it applies to tillering.

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  2. Hi, I mean the tip of the bow is trying to bend slightly sideways. (In danger of waggling one way or the other) It's one of the problems with English longbows being so narrow.
    Once they are fully braced and flexing ok to about 20" or so, it tends to settle down.
    A common beginner's mistake is to make the limb tips to their final narrow dimension (about 1/2" 12mm) and then find it tries to bend sideways.
    Leaving the tips a bit wide until nearly finished (I rough 'em out to 20mm) helps considerably. The centreline down the length of the bow, can easily shift a little and need some adjustment as the bow progresses and the wood settles, or a bend becomes apparent. Moving a tip across by a little by rasping some off one side can adjust the sting line and correct a tendency to go sideways before it really goes big time (at which point it can be a pig to recover).
    Often just 1/8 -1/4" and that will do the trick. Once it's all settled the last 5-6" of tip can be narrowed and blended in, and horn nocks fitted.
    It's especially a problem with bows with some reflex/recurve.
    As with most tillering it's about prevention rather than cure.
    Hope that makes sense.

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  3. I've added an extra picture and some more explanation.

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    Replies
    1. Thanks Del. Sorry about the finger

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