Author Topic: question on tillering process  (Read 3132 times)

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Offline Del the cat

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    • Derek Hutchison Native Wood Self Bows
Re: question on tillering process
« Reply #15 on: December 07, 2018, 12:26:16 pm »
I think the hardest thing is getting your eye in so that you can see the problems, especially on character staves or where heart and sapwood are a different colour and undulate, that can really can draw your eye.
A lot of people look but don't actually see.
When I pull a bow on the tiller and ask someone, which limb is stiffer? Or, where does it look stiff?
There is usually silence  ;D ... I have to say... it's not a trick question, just say what you feel, it's not absolute, it's all very subtle and each bit effects every other bit.
Once they stop worrying they are generally in the right ball park  :) .
If they can't see what's stiff, I'll ask where is it flexing most?
Del
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Offline bjrogg

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Re: question on tillering process
« Reply #16 on: December 07, 2018, 12:35:06 pm »
I'm not sure if this would work for anyone else, but it like to vice tiller. I've made enough bows in the draw length and weight group to have a fair idea how their going to look and feel. When I get to a floor tiller and I start working at the outer limbs and tips. I get them moving a little. I like to clamp handle area in vice with belly or back facing sideways. I bend limb by pushing or pulling from tip and also pushing or pulling tip towards handle. I watch limb bend. I like getting the outer limb moving and then just keep making more of the limb bend working my way in but always going back to the outer basically taking longer scraps until I get what looks like a fairly even bend in the vice and the tip moves about six inches. I do this to both limbs. Then I make notches and a string then I go to a low brace. Then I go to tree and usually it's pretty close to a even tiller with no hinges. If that's the case then I pull to my weight and keep perfecting my tiller until I get to draw length I want always exercising and then pulling to weight. I never use a tillering string. I just go to low brace a then as soon as I can I put enough twists in string to get to proper brace height.
Bjrogg

A hot cup of coffee and a beautiful sunrise

Offline Selfbowman

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Re: question on tillering process
« Reply #17 on: December 07, 2018, 07:51:03 pm »
I tend to follow what Weylin does . Floor tiller to brace. If it's close at brace you did your floor tillering and felling the reduction in mass in the limbs correctly. Then reduce mass to desired weight. I'm starting to lean slightly toward the tiller board though. It's going to take practice at that though to.
Preventing set is a demanding and patience task for sure.
Arvin
Well I'll say!!  Osage is king!!

Offline StickMark

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Re: question on tillering process
« Reply #18 on: December 07, 2018, 08:22:28 pm »
My thoughts:
The initial brace is exciting to me, because it is risky. Honestly, it is a rush. Get is too strong, and you have a 65 pound bow, without realizing it.  Here comes some set. 

I have been considering setting aside my "luggage scale", and building by feel.  But I would use my bows already built to check how an upper 40's bows feels compared to a 55# bow. 
Wonder where that would lead me.  I can tiller a bow to a pound or two, and I like working the numbers.  Likewise, tuning arrows is rewarding ( I tell my technology friends I reload, but with with wood).

 I am with George T: build it, tiller it, shoot it in.  let the bow sweat, meaning strung for four hours.  Then check tiller.  sand.  shoot a few dozen.  check tiller.  As a newbie, six years in, I need time, and extra wood,to sand paper it home.