Saturday, 10 January 2015

Two Bows, Primitive Yew and Hazel Warbow

With 2 bows being worked on, it's in danger of getting confused, so do pay attention at the back! ;-)
Yew Primitive:-

I sawed a thin slat of Yew from an off cut, actually it was a half log I had put to one side for firewood, but my other off cuts weren't wide enough.

The point of doing a thinnish slat is that it will more easily bend to the curve of the bow (where I deflexed it) and give a better glue line (especially if you clamp it at the ends where it meets the limb and will be very visible on the finished bow (ok, yes I forgot this and just used rubber strap. Hopefully I'll remember, or re-read this next time).

It then provides a raised surface which can be flattened on the belt sander to give a nice face to glue the riser block on to. It also gives a transition from riser to limb. On some bows this is a longer lamination known as a 'power lam'. I think its a daft name myself, a blend lam would be better IMO as that's what it's there for.
(Bear in mind that laminated bows aren't my thing, so maybe I have the terminology or reasoning wrong...)
Anyhow getting a nice blend on the fade without dipping into the limb can be tricky, and an extra thin lamination/slat/whatever helps. Note the grip area has only been narrowed slightly to allow for later adjustments. 'Nuff chat, here are some pics.

Hazel Warbow:-
The two pics on the left show the two staves side by side edge up, and back up for comparison.

Having roughed it out, just going by experience and starting at about 40mm wide at the grip I glued on some scaps of Yew as temporary nock overlays, filed in string grooves and got it on the tiller.
It flexed quite nicely with one limb being a bit stiffer. I took a bit off that limb with the draw knife... what gorgeous wood to work, it was like paring cheese, barely needed any effort.
I noticed the wood had some gey streaks and a hint of blue under the bark. I don't think this can be rot as the limb was off the ground and live when I cut it. It was also seasoned

high up in my garage where it's warmest and airy.
Back on the tiller and I heaved it back to about 70 odd pounds.... CRACK.... CRACK. Did I panic? Of course not (well just a tad) It was the bark on the back cracking off leaving a perfect surface underneath. There was one area popped off on each limb, that's natures strain gauge telling me the limbs are bending fairly evenly
As the curve and poundage seemed reasonably I'm now going to put some deflex into the grip. I've taken a 'before' pic to give me a reference.

Some time later:-
The warbow exploded on the tiller, dumping me onto my backside!
The deflex allowed it to be strung to about 3" of inches brace and I was flexing it to near 80# at somewhere near 26".

It seems to have smashed mid limb on both limbs. I'd been getting the outers moving more before heating in some reflex. My big worry was a nasty dip on the back at one edge of the grip...
At least it didn't break there!
I checked the moisture content and it was up at about 12-14% typical of wood in my garage.
Maybe the grey colouring was some problem with the wood, it certainly doesn't look like some 'good' Hazel I have....  Must admit warning bells were ringing when I first ran it through the band saw.
At least I hadn't wasted too much time on it. Shame I was hoping to use some of the off-cuts from the belly to make an experimental 35# flight bow... but I don't think the wood is up to it now... damn.
Ha, just confirmed it. I tried flexing one of the offcuts, it just snapped like a rotten dry stick. Seems like that would have been a good test before I started on the actual bow.

Onwards and upwards, I can concentrate of the Yew primitive.

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