Saturday, 27 July 2019
Character Warbow Work
Blimey, after 2 days of almost unbearable heat, it's now raining non stop, a good time to write up the blog! It was so hot last night, I went down stairs where it's cooler, opened up the big double patio doors and slept on the floor.
The stave is being worked down to a reasonable size and taper. I've taken the sapwood down and tried to get it following the undulations.
As I've reduced the belly I've uncovered a buried knot which has needed filling, I also fear I may have gone a tad thin near one of the big waggles, but only time will tell.
There's a fair bit of reflex near the grip on the lower limb, which I decided to steam out.
A little deflex makes warbows easier to get braced in the early stages of tillering, and a lot of reflex is a nightmare, as it makes it almost impossible to get 'em to brace without risking coming in under weight.
I feel for a bow with a long draw you can't afford to waste potential tip movement by having 3" of reflex.
Setting it up for steaming I found my old 5L plastic bottle steam chest had just about disintegrated. Fortunately I had a bottle of windscreen washer fluid that was almost empty, so I topped up the washer bottle in my car and cut some holes in the bottle for steam use. (Not forgetting a hole in the bottom to let any water out))
I set up for making 3 simultaneous corrections.
1. Pulling it down to put in some deflex to make the lower limb a better match for the upper and to make it about flat tip to tip. (I pull it too far to allow for it to settle back)
2. Sideways deflection to get the tips in line and to stop it trying to flip over sideways on the tiller.
3. Twist removal. (Wooden "spanner" clamped to tip and pulling down with rubber strap).
I left the steamer going for over an hour until it ran dry and switched off. There is a great temptation to take it off and see how it looks, but I resisted and left it overnight. I've taken a pic of it this morning against a straight edge, so that I'll be able to see how much it recovers over time before I start flexing it.
You can see the big waggle in the right limb in the bottom pic.
I've had it on the tiller on a long string and pulled it to about 80# it looks fairly even and the weak point i was worried about doesn't seem to be a problem. The really positive thing is that it is sitting much better on the tiller and not trying to flip over as the string alignment is now much better.
I'll maybe get some video later. https://youtu.be/2p_N3lcN8hw
I've eased off the outers and pulled it to 90# @25.5 from a 5.5" brace which is good progress.
That interpolates to about 110# when I allow for brace height. I may consider heat treating the belly near the grip and taking out a whisker of the deflex, but that will certainly wait for a day or so as it's only just been steamed.
The dilemma is, should one aim for a well tillered 100-105# character bow, or a 120# with the risk of ending up with a pile of firewood?
Slow and steady wins the day, when in doubt... don't.
I feel the extra thickness of sapwood near the grip will make it elastic rather than punchy, and it feels fairly safe... but experience has taught me that you can't actually tell which will explode.
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