Friday 12 October 2012

Maple II vs Maple I (update Full Draw Pic)


The mkII Maple is now shooting, there is a marked difference in the feel, with the mk1 I had to fiddle and fettle to get a good arrow flight, narrowing the grip down substantially at the arrow pass. MkII just shoots where you point, in fact it's even better than that!
It was grouping so well I had to shoot around my target to avoid smashing arrows, I worked around the edge starting from a 12o'clock position, as I got to the last arrow I thought 'I suppose I could shoot this one at the white squ....' thud the arrow had already hit home plumb centre of the white foam square!
MkII is at the top in both pics, upper pic is top limb belly side, second pic is viewing the back, you can see the mkII has a much chunkier grip.
The bow has bags of character, unstrung it looks to have a slight sideways curve to it and a line from nock to nock seems to run off centre through the arrow pass making it almost centreshot.
You can see in the top pic looking at the upper bow the very top edge looks much straighter than the lower edge. Oddly the mkI looks to be the opposite having it's lower edge straighter, maybe it's because they are from opposite sides of the tree, or maybe I just can't saw straight.
 It's not that simple though, as such a bow would want to twist in the had, but this doesn't. There is a twist in each stave  making one limb twisted relative to the other, and when braced it all sits square with a slight bias towards the arrow pass, it draws square and shoots true. You can also see how I managed to squeeze an extra half inch of length for the mkII (not quite sure how I did it!)
How do I know it's not all skew whiff?
I inadvertently shot it flipped lower limb uppermost, it shot just as sweet!


These bows are laid out straight in theory with perfect even straight limbs and an even taper, but in reality you have to follow the bends and twists of the wood to some extent, and that's the beauty of 'em.
Now I don't want to get over excited as it's not fully shot in or finished yet, but it's had about 65 arrows through it and it's looking good. The pics let you see the slightly different limb shape between the two bows, the £2 coin marks where the chrysals are in the mk1 and you can see the limb has been left wider in that area on the mkII. There is a slight colour difference on the back too, with the mkII the bark seemed to pop off leaving a more even slightly darker surface, some of which is the cambium, this has been lightly sanded, but I don't see any value in going down further and spoiling a nice even surface.
My son had a go and appreciated the workout pulling 50#. He's not quite to full draw as the lft arm is a bit bent, understandable as he couldn't be bothered with the bracer, and there are slight balance issues in the chair. It's now had over a 100 arrows through it and has settled down to a slight set, at brace the lower limb looks slightly weak, but this is due to it having some natural deflex while the upper has a hint of reflex. (there is a hint of distortion in the pic as the bow is canted with the top limb towards the camera)
I've tweaked the tiller a tiny bit since the shot above and it's just about arc of a circle. I'm almost tempted to re-heat treat the lower limb to let it relax back from it's slight set and toughen it up a tad in the inner third, I think it's a silly idea though as you have to know when to quit. The scale reads about 48#, but it's been at full draw for a few seconds and will have relaxed slightly.

I walked up to town through the woodland, heard a woodpecker and there was a good bit of fungi about. I noticed a tall skinny Ash tree which had buckled and bent over, it had a decent straight section about 6' tall below the break, so that might be a candidate for tidying up later, there was a bit of Hazel and one of Maple cut/broke too which might do for stick bows.
A guy may be coming over for a visit at the weekend, if so we can collect the staves and he might want some of the spoils.
I'll post a shot of each on the tiller later so you can see the different shape at full draw, and I'll have to shoot mkII through the chrono'.


3 comments:

  1. Never mind, I' cant saw straight either...

    Nice sister bows, I like them a lot.
    Do you think the difference between them comes from the layout or from the wood properties? Where they the two halves of a stem or a branch? Maybe it's like with kids, they're just different from the beginning.
    Good to see how you reacted to the chrysals by making it wider there.

    Oh: Love how you shoot through the door into the garage :)

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  2. Cheers, I think the difference comes from the extra width and the smoother nearly an arc of a circle tiller.
    There is a little set, mostly on the inner third and mostly the lower limb, I'd rather have a little set than chrysals any time.
    If I hold the bow with it's belly against a straight edge I can barely get one finger between grip and the the straight edge, which is pretty good, I think up to 2 fingers is ok, more than that is getting a bit too much. I think I went a bit mad try to go 'elliptical' with the first one version.
    The difference in tiller is easy to see but difficult to control, while still hitting the target poundage. It would be easy to make a 60# bow then adjust the tiller to perfection at 50#, but if the wood you have won't stand 60# then its all a bit tricky.

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  3. Oh, I forgot to say, they were two halves of a smallish trunk. An Oak fell in the woods and knocked over the Maple when it fell.

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