I met a new friend on line who's getting into making bows, he'd been reading the blog and I'd offered some advice on tillering. He'd also offered some Yew, but being an old and lazy git I didn't really feel up to the 90+ minute drive each way and heaving yew around (in my defence there were some home issues too at the time)
Anyhow he volunteered to bring the Yew over and spend some time in the garage, seeing what I get up to.
We had a great time, shot the Chinese repeater and my little crossbow, but most of the time was spent re-tillering a Warbow that he'd bought. It raised some interesting questions about tillering.
The bow was of about 130# and had apparently been tillered to 33" .
There's no way I'm going to heave an unknown bow back to 33" on the tiller, so, what draw weight and length did he actually want? About 100# at 32" was the target.
The dilemma is, do we pull it to 32" and see what it is now for comparison or just pull to 100# and see where we are starting from? Well boys and girls, can you guess which I went for?
Yes, pull to 100# 'cos that's the target weight. Well we didn't even pull it that far straight away as we watched it flex and critiqued the tiller... Which is the stiffer limb? Where is it bending most? Can you see/feel any thick spots?
Anyhow it was 100# at 27" which we could interpolate to the draw weight at 32".
Divide 100# by 27" to give pounds per inch and then multiply that by 32 which gives 118.5 or near as dammit 120# .
This isn't exact but it's gives me a good idea of how much wood I'll be taking off ... (reaches for big rasp)
After reducing the thick spots first, working the belly down and tidying the tips and nocks, it eventually ended up at about 100# @ 30" which was deemed to be close enough, allowing for some subsequent sanding (I'd just finished it with a cabinet scraper), shooting in, etc.
I think seeing how I work and think was quite enlightening, as of course I didn't do all the work at once, it was up and down on the tiller umpteen times. I also did a quick demo of how to put a burr on a cabinet scraper. On the other hand I was, rather rushing and the bow was clattering around with one end resting on my vice with a strip of carpet on it. Normally I'd have clamped it and taken a little more care, working in shorter burst, but we were on a fairly tight time scale. It can get a bit busy trying to show all the processes in a four hour burst (tea and toast breaks of course!)
Once he'd gone I sneaked upstairs for a cat nap, and was out like a light.
Next day (yesterday) I ran the Yew through the bandsaw, wrote the date on it and painted the ends with PVA. The first tidy up through the bandsaw is basically taking the corners off. A half log is semicircle so that gets reduced to more of a D and a Quarter log is pretty much triangular, so the corners are taken off. Anything heavy is reduced in stages, one log was big knots along one side with only a relatively narrow clear strip and I had to take most of the knotty side off first to provide a flat face that would run flat on the bandsaw table for the next cut. I have the far end of the log supported on a roller, but even so it's about at the limit of what I can manage single handed.
The first pics shows the load of Yew with just one piece having been tidied up through the bandsaw.
The final pic shows the 4 good staves (one is barely visible against the garage floor) and a log which didn't really have anything suitable in it, (it may have had a single billet, but you really want billets as pairs, its on the habitat pile in the garden now for the bugs and beetles to enjoy).
The biggest stave may make two bows, but it's best left for now as the position of various knots may mean it's better to have one good warbow stave than two skinny marginal staves. It's the old adage "when in doubt leave it"
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