Trad Gang
Main Boards => The Bowyer's Bench => Topic started by: Wolftrail on May 17, 2015, 12:51:00 PM
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Seem to get conflicting responses as to what is correct here for bow weight. AMO standards state that draw length is from back of bow to arrow nock groove. So where is the actual draw weight measured from the pivot point or back....?
My tiller stick is marked off from the belly.
(http://i652.photobucket.com/albums/uu250/dynolude/bowdraw.gif)
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True draw length + 1,75" = AMO length
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So bow weight measured on True draw length (as shown in picture) is AMO draw weight.
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So my tiller stick is marked correctly, makes sense because fistmele is from True draw length.
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Sorry, all says above right
when 'True draw length'=26.25"
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Originally posted by Bakh:
Sorry, all says above right
when 'True draw length'=26.25"
You lost me. True draw length'=26.25"...? as to what relevance..?
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the way i understand it is( which really does not make sense- anyway..) is the distance from the shoulder of the arrow nock to the deepest part of the grip( pivot point) plus 1 3/4".
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so your tiller stick ( like mine!!) is marked INCORRECTLY :(
nothing to do with fistmele- which is simply brace height---i know all unnecessarily confusing :confused:
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Originally posted by fujimo:
so your tiller stick ( like mine!!) is marked INCORRECTLY :(
nothing to do with fistmele- which is simply brace height---i know all unnecessarily confusing :confused:
I'm talking about weight here not draw. My last takedown bow is 2" at rest so why add another 1 3/4" of dead length....? See what I'm getting at here. :confused: Basically what I'm saying is you have no bow weight for that 1 3/4" extra.
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From AMO Standards...
"AMO Draw Length is the distance to Pivot Point plus 1 3/4". This establishes a constant when compared to the variations of profile of the back of bows. Thus - 26 1/4" from Pivot Point is equivalent to 28" draw length and is the draw length at which manufacturers weigh and mark conventional bows."
"For the purpose of uniform bow weight designation, bow weight is the force required to draw the bow string 26 1/4" from the Pivot Point. The weight will be marked on the bow as being taken at a 28" draw (26 1/4 + 1 3/4 = 28") SEE DRAW LENGTH STANDARD."
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Thanks Junk for the explanation. I also got to thinking; in the hunting and trapping regulations Synopsis states that a bows weight is that of the hunters draw length. Quote unquote "AMO Draw Length"
That clears up a whole lot of non-sense. :goldtooth:
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Clear as mud, think I need to have another cup of coffee and then come back and read this again. Nothing wrong with the explanations, I am just not awake enough to think yet!
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Clear as mud, think I need to have another cup of coffee and then come back and read this again. Nothing wrong with the explanations, I am just not awake enough to think yet!
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I guess if one wants to know the actual weight being drawn by any given archer and with any any given bow, one needs to go with the arrow marked (at the back of the bow would be conveniant) while drawn and then weigh it at that draw length.
It seems that the varied methods of measuring weight and draw length can be confusng when using those methods to arrive at chrono speeds, etc. It's not very "trad", but my prefered yardstick of performance is the chrono. Not a speed demon, but just a way to compare any project in hand with previous projects.
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If you don't use the amo method of determining draw length you won't be comparing apples to apples. For example a hill style bow is less thick from the pivot point than a thick recurve riser. If you determined weight by measuring to the back of the bow the longbow would be drawn further than the recurve giving it a longer power stroke. The benefit of using the amo measurement when comparing bows is both will have the same power stroke. For example a horse bow drawn to 32" measuring from the back of the bow is actually drawn closer to 33" amo. Compare that to a recurve drawn to 28" to the back of the bow and the recurve gives up nearly 5" of power stroke. You can't make a honest comparison.
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Sorry about the double post this morning, told you I needed more coffee! Makes a lot more sense now.
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Not every bow is created equal; agreed.
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Oh, I agree completely, Ben. I look at it from two points of view. One being yours, which allows ready comparison of all bows across the board and then the comparison of my own bows that are, thus far, ASL style with grips right at 1.75" to 2" deep. Speaking only of glass lam styles.
Being equal across the board, as you suggest, allows for more universal comparisons.