Selfbow Tillering Help

[Tom Alker]

Hey Folks,

Back again with the self bow, After a club shoot a few weeks back perry noticed small chrysals forming on the bottom limb but i think i fixed the problem area and they don't seem to be getting any worse.

Can you guys notice anything wrong with the picture? I feel maybe the right limb (top) has a small stiff spot towards the tip. The chrysals i was getting are on the left limb (bottom) so let me know if you see any problem areas.

It seems the bottom limb (left) is bending nicely so im not sure why chrysals started forming.

Cheers, Tom.


Specs:
78'' Long
#58 DW
28" Draw

[Hamish]

Is that spotted gum or ironbark? I find they can chrysal as often as not for no good reason, despite a decent tiller. Just temperamental, unless it was overstrained earlier in the tillering process.
I'd be surprised if the chrysal got worse, unless you increase the draw length. A 78" long bow really shouldn't get chrysals with a 28" draw, and I don't think its your fault. I have seen plenty of eucalyptus bows with lovely tiller, yet show chrysals. I personally don't like seeing them but the bows seem to shoot okay. I'm pretty sure if you can get hold of some proven bow timber you will avoid chrysals totally.

Another option is to try wider flatter limbs, 2.5"(but shorter in length68-72"), narrow the last foot of the tips. Wider limbed flatbows seem to be more resistant design against chrysalling, with our Eucalypts.
Hamish.

[Tom Alker]

Is that spotted gum or ironbark?
Hamish.

I'm fairly sure it's bloodwood.

I find they can chrysal as often as not for no good reason, despite a decent tiller. Just temperamental, unless it was overstrained earlier in the tillering process.

Yeah I think the chrysals showed up quite a while ago, Once they were pointed out to me i changed the tiller slightly to try to relieve some stress on the areas with chrysals, they don't appear to be getting worse recently which i guess is a good sign.

Thanks for your reply hamish, my next bow will have very wide limbs as most of my bows have been quite thin, id like to try a safer design