Thursday, 28 February 2013

Yew Longbow More Heat

I got the bow trimmed up to about the right dimensions and cleaned up the back. Putting it on the tiller it felt a bit under powered so I got it braced and tried it. 50# at about 26".
I'm aiming for 55# at 28" so I was a bit worried, it looked good on the tiller but looks more like it should be coming back to 20" not 26".
I cleaned up the back to a decent finish and rounded the belly, pulling it to 28" and it was under 50#.

Not good enough, must try harder! Some of the deflex had come back, so I've decided to re-temper the belly and get a hint of reflex into it this time.
I've put 4 layers of masking tape over the sapwood and strapped it up  with an inch or two of reflex. In the smaller pic you can see the limb nearest the camera clamped up with some reflex while the far one still has some deflex
Where I'm heating it I've clamped a couple of off-cuts of wood to keep the heat from the sides of the bow, it also helps to channel the hot air along the belly aiding even heating. I've got one limb done now and I'll unclamp it and do the other tomorrow.
Update:- Ive had a look and the tempering seems to be better this time, the belly is darker, and having unclamped it, there was less spring-back this time. I might do the other limb tonight, so it will be re-hydrated by the weekend.

If I can get anything over 50# at 28" I'll be happy, I don't want to shorten the bow any further, and chasing draw weight too much can be a self defeating task in my experience.

The bow is fairly chunky in cross section with the pith line showing on the inner 1/3 of the belly, it shows how little heartwood I had to play with. I think it's going to turn into a fine bow, it'll just take some more work.

Meanwhile I'm messing about with the bonkers bow, which is actually shooting now! It's symmetrical about the centreline, e.g Big long narrow grip section so the working limbs end up being about the same length.

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