Author Topic: Tillering advice please  (Read 4005 times)

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Offline DC

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Tillering advice please
« on: December 08, 2016, 08:15:53 pm »
I got the new limb on and out to about 25" going for 27 1/2-28 . I've got a few pounds to play with. I made a tracing of the bow to monitor set and it's taken a bit right where the red arrow is. I think you can see it's a touch thinner there. If I thin it out where the blue lines are will that relieve the stress a bit on that spot or will it just make a bigger spot for set to happen? It's also got a bit of set mid-limb on the other side but that's where I took some deflex out so I'm not sure if I can do much but reflex and heat treat that.

Offline DC

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Re: Tillering advice please
« Reply #1 on: December 08, 2016, 08:29:20 pm »
Here's an unbraced picture. It's been fun too make but I think it's going to be the ugliest bow I'v seen ;D ;D

Offline SLIMBOB

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Re: Tillering advice please
« Reply #2 on: December 08, 2016, 10:16:16 pm »
Wow.  Thats a doozy!  I would have straightened it if it were me.  I think.  I dont think I would take any off at the blue lines. 
Liberty, In God We Trust, E Pluribus Unum.  Distinctly American Values.

Offline aaron

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Re: Tillering advice please
« Reply #3 on: December 08, 2016, 11:14:38 pm »
Oh my god- I am in love with this bow!
Ilwaco, Washington, USA
"Good wood makes great bows, but bad wood makes great bowyers"

Offline aaron

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Re: Tillering advice please
« Reply #4 on: December 08, 2016, 11:17:27 pm »
I wouldn't take any off at the blue line on the left (the fade), I might take a tiny bit off of the blue line on the right. I would also take a tiny bit off everywhere else.
Ilwaco, Washington, USA
"Good wood makes great bows, but bad wood makes great bowyers"

Offline Pat B

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Re: Tillering advice please
« Reply #5 on: December 08, 2016, 11:30:08 pm »
 You can either tiller it out so the whooptydoo bends with the rest of the limb or leave it stiff and tiller the limb beyond the hump. The first option is the best for the bow but the hardest for the bowyer.  Either way it's gonna be difficult.  Which ever way you go I'd put the whooptydoo in the bottom limb. That limb is gonna be stiffer no matter what.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline DC

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Re: Tillering advice please
« Reply #6 on: December 08, 2016, 11:32:56 pm »
I was thinking that a spot that is taking set is kinda like a hinge- it's an over stressed area. So I thought I should maybe treat it like a hinge and even out the stress surrounding it. Does that make sense?

Offline DC

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Re: Tillering advice please
« Reply #7 on: December 08, 2016, 11:39:20 pm »
You can either tiller it out so the whooptydoo bends with the rest of the limb or leave it stiff and tiller the limb beyond the hump. The first option is the best for the bow but the hardest for the bowyer.  Either way it's gonna be difficult.  Which ever way you go I'd put the whooptydoo in the bottom limb. That limb is gonna be stiffer no matter what.

I am considering making it the bottom limb. Right now the string alignment is better if it is the top limb and where the arrow pass would be is better if it was the top limb but neither are insurmountable.

It's a strange combo, one limb is snakey and the other is roller coastery

Offline Pat B

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Re: Tillering advice please
« Reply #8 on: December 08, 2016, 11:43:36 pm »
Take your time and scrape thoughtfully. This bow can teach you lots about bending wood.  ;)  ...and patience.   :-\
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline DC

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Re: Tillering advice please
« Reply #9 on: December 09, 2016, 12:02:12 am »
The big bend is actually moving and responds quite well. The little wiggle further out the limb was a bear to get moving.

Offline bow101

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Re: Tillering advice please
« Reply #10 on: December 09, 2016, 12:06:06 am »
I think it looks quite radical   8)   hopefully ya get 'er shooting.
"The privilege of a lifetime is being who you are."  Joseph Campbell

Offline loon

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Re: Tillering advice please
« Reply #11 on: December 09, 2016, 03:31:24 am »
Well, that really makes me begin to appreciate wood for bows, especially if you get it working.. it's so unique or something

Offline simson

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Re: Tillering advice please
« Reply #12 on: December 09, 2016, 03:39:50 am »
Now that's a thing to play with!
You should monitor the different stadium to study the bending, What I mean is something like here:

http://www.primitivearcher.com/smf/index.php/topic,41217.60.html

see page 5



Simon
Bavaria, Germany

mikekeswick

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Re: Tillering advice please
« Reply #13 on: December 09, 2016, 04:11:42 am »
If it is already bending and showing set you need to reduce the whole of the limb a bit and not touch the hump. When you have a large/sharply deflexed area like that the forces are concentrated there so with a normal correct thickness taper that area will bend too much.

Offline DC

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Re: Tillering advice please
« Reply #14 on: December 09, 2016, 01:13:59 pm »
Now that's a thing to play with!
You should monitor the different stadium to study the bending, What I mean is something like here:

http://www.primitivearcher.com/smf/index.php/topic,41217.60.html

see page 5

I remember that bow and that was back when I was Don Case, not DC. How do you hold the bow long enough and steady enough to trace it accurately without over stressing the bow?