Primitive Archer
Main Discussion Area => Bows => Topic started by: DC on November 16, 2014, 07:57:12 pm
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I am closing in on the latest bow. It's 90% (or so) tillered. I was measuring +- tiller and got it within 1/4" so I decided to make the + the top. I reversed the string, braced it and measured the tiller again. Now there is a full 1/2" difference. Reversed the string and it went back to within 1/4". I'm using a timber hitch at the bottom if that matters. What is doing this?
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Diference in nock size/shape can throw it off by holding a different size loop higher/lower. Furthermore a timber hitch can hold the tip different than a loop would just hand from the nock.
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Thanks Marc. I wondered if that was it, that's why I mentioned that I was using a timber hitch. I'll leave it until I've shot a bunch of arrows. You wouldn't think it would make that much difference. Fussy little dickens, aren't they :)
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I don't use the timber hitch because of an inability to get it right, I've friends that do and they always put it on the top.
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Measuring +/- tiller on a braced selfbow is worthless IMO. The best place to see proper tiller is at full draw. Usually there are too many irregularities in selfbows to get a good reading at brace. That is a FG think. If you machine a bow, you can do that but not with selfbows. If your bow looks good all around at 90% completion I'd say take it out and shoot it.
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Good point pat, one of the things I've been having to do here in Nevada is just hope the tiller is positive when it feels right because I can't see full draw.
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Does the stave have any prop twists? Jawge
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Does the stave have any prop twists? Jawge
No, it's quite straight.
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agree with Pat,, measuring a self bow at brace can be deceiving,, the way it looks at full draw is what counts,, you can use a pulley to get the basic idea,, put that will sometimes look different than drawn by hand,, best to take a pic at full draw to see that,,or have your expert peanut gallery comment :) :) :)
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Adjusting for a 1/2" positive or negative would cause a pretty high weight loss. I have cut 1" off the lighter limb a couple of times when I was too close to target weight. No comment on the string I use double loops on everything.
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Has one limb taken significantly more set than the other? +1 for a full draw with an arrow picture.
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When you reversed the string you put the timber hitch up top?
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s there a bit of uneven wood removal going on here in that there is a difference in measurement depending on which side you measure? You may have a leaner. Had a few of those myself over the years.
Interesting problem.
It's a mystery
Jawge
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Here's some pictures. It looks to me like the top limb could use a couple of scrapes.
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Looks darn close. I might scrape the inners just a touch.