Monday, 14 October 2013

Elm Warbow Heat Treated

I got one limb of the Elm warbow heat treated yesterday afternoon. I strapped it down to remove some of the slight set and to try to straighten that kink a bit. One the first section was heated I set a kitchen timer to 4 minutes and moved it a long a bit each time the timer rang. Well it's not easy cooking Sunday dinner when you stop every 4 minutes, but both the dinner and the limb got cooked nicely.
Later in the evening I did the second limb, and while that was cooking I reduced the draw weight of a Sycamore longbow that I'd been asked to look at.
You can see from the pics, the kink is still there, but the overall run of the limb is straighter, so it should be easier to judge the curve of the bow on the tiller.
The Elm seems to like the heat treatment as the wood definitely feels harder, and using an ordinary string I can't string it now, so it's obviously gained some weight. Hopefully this means I can remove some wood to get the tiller right without ending up under weight. I'll also be removing the cambium which is about 3mm thick, it doesn't seem to be popping off like it does with Yew. It's served it's purpose in protecting the back during heat treating. The corners can get rounded and the whole bow tidied up a bit now. I think 80-90% of the work is done. It seems that you need to get it right earlier in the process with a warbow for fear of coming in under weight, it's just tricky as it's so much harder to flex the bow, and damn near impossible to string it early on.

The game plan is going far too well... I expect something will happen to bite me on the backside!
I'm rather disappointed with my fitness level, I'm going back to doing push ups every night and morning in attempt to build up some strength for the spate of warbows I'm building. The problem with fitness is it's hard won and easily lost. Sitting in front of a computer doesn't help and I've not been shooting much. I'll have to shoot some through my heaviest bow every evening to help build up.
One problem is I don't have any bows tillered to 32" which is one reason I'm making the Elm Warbow. Best training for shooting warbows is actually shooting warbows. I don't s'pose sanding and painting ceilings does any harm either!

Tad worried, I've taken too much off the inner limbs. The tiller is more even now and the set has gone. It's about 80# at 28 on a low brace, which if we assume 4# per inch would give 96# at 32"
The lighting is a bit weird which makes it look odd and a bit hingy at the grip.
Ignore the knots and wiggles and hold up a cd, the curve isn't too bad... yes it is working a tad hard in the middle but the tips haven't yet been reduced to the skinny 1/2" of a typical Mary rose bow. I've added an elipse drawn in paint, it helps show the errors.
Right limb is a tad stiff mid limb too, but that kink makes it tricky to view objectively.
I need to ease of the tips a bit, increase the brace, although I could always re-do the heat treatment near the grip where a fair bit of wood has come off.
My ace in the hole is I can take a couple of inches off each tip as it's about the maximum Mary Rose length.
Couple of days at work now, which is probably a good thing as it will stop me fiddling with it.
So to summarise... Idunno... :-)

1 comment:

  1. Great bow, hope to see it finished.
    I'm doing nearly the same with ash that i get here, pyrinees mountains, Spain. I haven't managed yet to get a longbow of more than 50# 28.

    Keep on that nice bow