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poundage question

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  • Jeff / Luminesce
    When one twists the string to increase the brace height does it increase the poundage as well?
    Message 1 of 24 , Mar 31 2:33 PM
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      When one twists the string to increase the brace height does it
      increase the poundage as well?
    • Carolus Eulenhorst
      No. The poundage is determined by the length of the draw, not the brace height. As it changes the resting weight of the bow, it will change the power curve
      Message 2 of 24 , Apr 1, 2004
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        No. The poundage is determined by the length of the draw, not the brace
        height. As it changes the resting weight of the bow, it will change the
        power curve and therefore affects the flight of the arrow. There are
        many changes involved here however, string length, tip placement, tip
        angle, travel distance of the arrow under power, etc. All of which
        results in fine tuning the arrow's flight but no significant change to
        the gross dynamics of the bow.
        Carolus
        On Wed, 31 Mar 2004 22:33:02 -0000 "Jeff / Luminesce"
        <luminesce_duir@...> writes:
        > When one twists the string to increase the brace height does it
        > increase the poundage as well?

        ________________________________________________________________
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      • RJ Bachner
        ... Heya To my understanding it does not in fact increase the effective draw weight at full draw but it does increase the amount of strain the bow must abide
        Message 3 of 24 , Apr 1, 2004
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          On Wed, 31 Mar 2004 22:33:02 -0000, you, with reckless abandon, wrote:

          >When one twists the string to increase the brace height does it
          >increase the poundage as well?
          >

          Heya

          To my understanding it does not in fact increase the effective draw weight at full draw but it does
          increase the amount of strain the bow must abide at brace height and it does shorten the powerstroke
          of the bow.

          so in effect you loose a little and gain a little which is greater you must test for your self.



          Herre Ragi "warm Bear" Wul├×arsson of the shire, Isle du Dragon Dormant.
          (Sometimes known as RJ Bachner)

          Northern shores, East Kingdom SCA.
          ragi@...

          Come visit the Archery diy Pages @
          www.diy.brokenaxe.ca
          and the shoppe @
          www.shoppe.brokenaxe.ca

          House of the broken axe.
          www.brokenaxe.ca
        • Siegfried Sebastian Faust
          ... While you are right that the length of the draw changes the poundage Carolus ... the brace height will ALSO do that. If you shorten your string to have a
          Message 4 of 24 , Apr 1, 2004
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            At 01:49 PM 4/1/2004, Carolus Eulenhorst wrote:
            >No. The poundage is determined by the length of the draw, not the brace
            >height.

            While you are right that the length of the draw changes the poundage
            Carolus ... the brace height will ALSO do that.

            If you shorten your string to have a higher brace height, the limbs are
            more flexed because of the shorter string, when you pull it to the same
            point, the limbs will be even more flexed that they would have been with
            the longer string, and therefore the poundage will have increased.

            However, with the longer brace height, you will have a shorter power
            stroke, therefore robbing energy.

            I, and others, use this effect all the time on combat crossbows to 'tune'
            them to be around the 600 in-lb mark ... loosen the string to drop poundage
            but increase power stroke, shorten the string to up poundage and lose power
            stroke.

            It isn't a linear curve, and therefore you can often adjust (for combat
            archery) an 'illegal' 625 in-lb crossbow to be a legal 600 in-lb crossbow
            through these adjustments.

            Siegfried



            ___________________________________________________________________________
            THL Siegfried Sebastian Faust http://crossbows.biz/
            Barony of Highland Foorde Baronial Web Minister & Archery Marshal
            Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
            http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
          • atruemark@aol.com
            In a message dated 4/1/04 1:46:03 PM Pacific Standard Time, crossbow@freeshell.org writes: If you shorten your string to have a higher brace height, the limbs
            Message 5 of 24 , Apr 1, 2004
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              In a message dated 4/1/04 1:46:03 PM Pacific Standard Time,
              crossbow@... writes:
              If you shorten your string to have a higher brace height, the limbs are
              more flexed because of the shorter string, when you pull it to the same
              point, the limbs will be even more flexed that they would have been with
              the longer string, and therefore the poundage will have increased.

              However, with the longer brace height, you will have a shorter power
              stroke, therefore robbing energy.

              I, and others, use this effect all the time on combat crossbows to 'tune'
              them to be around the 600 in-lb mark ... loosen the string to drop poundage
              but increase power stroke, shorten the string to up poundage and lose power
              stroke.

              It isn't a linear curve, and therefore you can often adjust (for combat
              archery) an 'illegal' 625 in-lb crossbow to be a legal 600 in-lb crossbow
              through these adjustments.

              Siegfried

              This is one of those subjects in archery where everyone is saying the same
              thing, but using different terminology to describe the effect. In this case, I
              believe Carolus to be correct.

              Think of it this way. Imagine your bow as being perfectly straight from
              riser to limb tip. Now brace it to 6". It will have stored "X" amount of energy
              in the limbs. Draw it back to your anchor point and it will have "X" amount
              of more stored energy in the limb. Now twist the string up a bit and increase
              the brace height to 7". Have you "increased the poundage?" No. All you've
              done is increase the stored energy in the limb for that increased brace height.
              If you draw back to your regular anchor, you are still storing the same
              amount of energy as you would have with a 6" brace height.

              What is different is the amount of time the string is in contact with the
              arrow, which is what fools a lot of folks. The lower the brace height (within
              good operating parameters for the style of bow) the more of the stored energy
              makes it into the arrow, increasing arrow speed off the bow. The higher the
              brace height, the less time the string is in contact with the arrow, slowing the
              arrow speed. These differences can be quite dramatic and allow the shooter to
              fine tune for things like over/under spine in the bow and arrow relationship.

              Again, the net effect is the same as both of you have described it, but the
              mechanism for getting there is as described above. The poundage does not
              change, per se, but the amount of energy transferal increases and decreases
              according to brace height.

              Regards,

              Andras Truemark


              [Non-text portions of this message have been removed]
            • georgeledbury@aol.com
              NO [Non-text portions of this message have been removed]
              Message 6 of 24 , Apr 1, 2004
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                NO


                [Non-text portions of this message have been removed]
              • Carl West
                ... Same amount of available energy? maybe. Different draw weight? maybe. Different geometry? certainly. Someone with a bow-scale, a measuring tape, graph
                Message 7 of 24 , Apr 1, 2004
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                  atruemark@... wrote:
                  >
                  > In a message dated 4/1/04 1:46:03 PM Pacific Standard Time,
                  > crossbow@... writes:
                  > > If you shorten your string to have a higher brace height, the limbs are
                  > > more flexed because of the shorter string, when you pull it to the same
                  > > point, the limbs will be even more flexed that they would have been with
                  > > the longer string, and therefore the poundage will have increased.



                  > Think of it this way. Imagine your bow as being perfectly straight from
                  > riser to limb tip. Now brace it to 6". It will have stored "X" amount of energy
                  > in the limbs. Draw it back to your anchor point and it will have "X" amount
                  > of more stored energy in the limb. Now twist the string up a bit and increase
                  > the brace height to 7". Have you "increased the poundage?" No. All you've
                  > done is increase the stored energy in the limb for that increased brace height.
                  > If you draw back to your regular anchor, you are still storing the same
                  > amount of energy as you would have with a 6" brace height.


                  Same amount of available energy? maybe.
                  Different draw weight? maybe.
                  Different geometry? certainly.

                  Someone with a bow-scale, a measuring tape, graph paper, a bow and a little time want to make a chart or two?

                  This guy addresses some of the issues, but doesn't speak to the question of draw-weight v. brace-height:
                  http://homepage.ntlworld.com/joetapley/bh.htm
                  nor does he give any citations of of authorities or research.
                  There's no proof that he didn't develop this through rectal extraction.

                  He certainly has a lot of stuff on archery on his site. Trim the URL to see. Not all of what he says makes sense to me, but, it's late.

                  -- Fritz


                  If you try to 'reply' to me without fixing the dot, your reply
                  will go into a 'special' mailbox reserved for spam. See below.


                  --
                  Carl West carlDOTwest@... http://carl.west.home.comcast.net

                  >>>>>>>> change the 'DOT' to '.' to email me <<<<<<<<<<<<

                  "Clutter"? This is an object-rich environment.
                • atruemark@aol.com
                  I agree with Carl that my earlier explanation was simplistic. It s also true, in the same way that saying a chunk of lead is solid, which it is in a real
                  Message 8 of 24 , Apr 1, 2004
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                    I agree with Carl that my earlier explanation was simplistic. It's also
                    true, in the same way that saying a chunk of lead is solid, which it is in a real
                    world kind of way. On an atomic level, however, it isn't - in fact, it's full
                    of space and in no way a solid. So to with brace height vs poundage. My
                    earlier explanation is true, in a general, real world sense. Technically,
                    however, all sorts of factors come into play - bow profile, materials, even the mass
                    of the string. This is from Archery; The Technical Side, of the Legends of
                    the Longbow series compiled by Glenn St. Charles, in an article written in
                    March 1931 by C.N. Hickman.

                    "This means that a bow braced high does not require much more strength to
                    hold, when fully drawn, than if it were braced low....and for all practical
                    bracing heights, the force-draw curves merge into one common curve near the end
                    of a full draw." (page 19, paragraph 5). Further, "The drawing force for a
                    full draw is almost independent of the bracing height of the bow string."
                    (page 21, first point under Summary) and "The arrow velocity increases with
                    increase in bracing height up to a certain point (if starting with zero brace
                    height), after which it slowly decreases with additional increases in bracing
                    height." (page 21, point 5 under Summary).

                    So, without taking into account a variety of factors, it is safe to say that
                    the major impact that lowering or raising brace height has on performance is
                    not poundage related, but more in how long the string stays in contact with the
                    arrow, thus transfering stored energy into the arrow.

                    Regards,

                    Andras Truemark


                    [Non-text portions of this message have been removed]
                  • Carolus Eulenhorst
                    I don t find this at all. Testing three crossbows and four recurves (three working recurves and one semi-working recurve), I find the poundage the same at the
                    Message 9 of 24 , Apr 1, 2004
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                      I don't find this at all. Testing three crossbows and four recurves
                      (three working recurves and one semi-working recurve), I find the
                      poundage the same at the same draw length regardless of where I have the
                      brace height..The bow is flexed the same amount at the same draw length
                      though it is, indeed, flexed more at rest with a higher brace height. In
                      forty years of shooting I have never found changing the brace height to
                      change the total draw weight.

                      The effect you see is not the result of poundage change but rather
                      distance change. For example, a crossbow braced at 4 inches and drawn 10
                      inches with a draw weight of 62.5 pounds will yield 625 inch pounds of
                      pull. If the brace height is raised to 4.4 inches it reduces the draw
                      length to 9.6 inches. When multiplied against the same 62.5 pound pull
                      the result is 600 inch pounds. This is what has led to many
                      misunderstandings about the power of crossbows on the combat field. Some
                      would say that a 62.5 pound crossbow in too powerful but they are
                      ignoring the fact that the power curve is reduced and thus the work done
                      on the bolt is decreased resulting in less impact.

                      If you do actually see the poundage change I would like more information
                      on the poundages at each brace height, draw lengths, and construction of
                      the bows.
                      Carolus
                      On Thu, 01 Apr 2004 16:39:14 -0500 Siegfried Sebastian Faust
                      <crossbow@...> writes:
                      > At 01:49 PM 4/1/2004, Carolus Eulenhorst wrote:
                      > >No. The poundage is determined by the length of the draw, not the
                      > brace
                      > >height.
                      >
                      > While you are right that the length of the draw changes the poundage
                      >
                      > Carolus ... the brace height will ALSO do that.
                      >
                      > If you shorten your string to have a higher brace height, the limbs
                      > are
                      > more flexed because of the shorter string, when you pull it to the
                      > same
                      > point, the limbs will be even more flexed that they would have been
                      > with
                      > the longer string, and therefore the poundage will have increased.
                      >
                      > However, with the longer brace height, you will have a shorter power
                      >
                      > stroke, therefore robbing energy.
                      >
                      > I, and others, use this effect all the time on combat crossbows to
                      > 'tune'
                      > them to be around the 600 in-lb mark ... loosen the string to drop
                      > poundage
                      > but increase power stroke, shorten the string to up poundage and
                      > lose power
                      > stroke.
                      >
                      > It isn't a linear curve, and therefore you can often adjust (for
                      > combat
                      > archery) an 'illegal' 625 in-lb crossbow to be a legal 600 in-lb
                      > crossbow
                      > through these adjustments.
                      >
                      > Siegfried

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                    • Siegfried Sebastian Faust
                      Ok Carolus, I see a slight error here, and I want to try to explain this, if the explantion doesn t work, I ll draw a graphic ... just let me know. I find the
                      Message 10 of 24 , Apr 2, 2004
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                        Ok Carolus, I see a slight error here, and I want to try to explain this,
                        if the explantion doesn't work, I'll draw a graphic ... just let me know.

                        I find the
                        >poundage the same at the same draw length regardless of where I have the
                        >brace height..The bow is flexed the same amount at the same draw length
                        >though it is, indeed, flexed more at rest with a higher brace height.
                        [snip]
                        >The effect you see is not the result of poundage change but rather
                        >distance change. For example, a crossbow braced at 4 inches and drawn 10
                        >inches with a draw weight of 62.5 pounds will yield 625 inch pounds of
                        >pull. If the brace height is raised to 4.4 inches it reduces the draw
                        >length to 9.6 inches. When multiplied against the same 62.5 pound pull
                        >the result is 600 inch pounds.
                        [snip]
                        >If you do actually see the poundage change I would like more information
                        >on the poundages at each brace height, draw lengths, and construction of
                        >the bows.

                        Ok Carolus, simple physics ... and I'm going to use crossbows as an
                        example, just because I find it a better mental model.

                        Ok, Let's say you have a 28" wide crossbow prod, and a 26" long
                        string. That gives you some amount of brace height.

                        Ok, now imagine the crossbow drawn back and cocked. Assume now, that
                        there is a 1" wide nut/shelf/etc it is in.

                        If you measure the length now, of the string on either side of the nut to
                        the tip. You will find it is 12.5" ... half the width of the string, after
                        the 1" of nut is taken into consideration. So the angle the prod is being
                        held at, is to allow for a 12.5" length of string on either side of it to
                        exist. Measure the poundage here.

                        Ok, now, take the string off and twist it tighter until it is only 25" long.

                        Ok, now put it back on the crossbow, and you will have a higher brace
                        height. Agreed?

                        So now, pull back/cock the crossbow. Do the same measurements. Now, there
                        is only 12" on either side of string. By simple physics, the prod has been
                        pulled back farther. There is no other way around it. Now, unless this
                        prod 'somehow' has magical properties that give it a smooth unchanging
                        poundage (I know of none), the fact that it is being stressed farther,
                        means it took more force to get it there, and therefore, if you put a
                        bowscale on it now, the poundage will be higher.

                        Now, as stated, the power stroke is now shorter, as the string stops
                        sooner, and this counteracts 'somewhat' the difference. However, each bow
                        is different, and some stringheight/poundage is the optimum for that
                        bow/prod, others are less efficient, therefore, depending upon the bow, you
                        can adjust it's poundage, and it's power, by playing with that, because in
                        my experience, it isn't a smooth curve.

                        Siegfried
                        (Who will also sit down and do lots of string pulling on one of his
                        crossbows for ya if he has to *grin*)



                        ___________________________________________________________________________
                        THL Siegfried Sebastian Faust http://crossbows.biz/
                        Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                        Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                        http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
                      • eulenhorst@juno.com
                        No. The pre-stress is higher but the total stress is identical. A spring tensioned to the same point will only show a certain poundage regardless of the
                        Message 11 of 24 , Apr 2, 2004
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                          No. The pre-stress is higher but the total stress is identical. A spring tensioned to the same point will only show a certain poundage regardless of the prestress. The archery mechanics site posted earlier has a good discussion of spring loading and prestress under plunger buttons. My results are empirical based on actual tests with a bow scale, not theoretical.

                          In Service to the dream
                          Carolus von Eulenhorst
                          eulenhorst@...
                          BTW, that mechanics site has some references on the home page and seems well grounded.
                          CvE

                          -- Siegfried Sebastian Faust <crossbow@...> wrote:
                          Ok Carolus, I see a slight error here, and I want to try to explain this,
                          if the explantion doesn't work, I'll draw a graphic ... just let me know.

                          I find the
                          >poundage the same at the same draw length regardless of where I have the
                          >brace height..The bow is flexed the same amount at the same draw length
                          >though it is, indeed, flexed more at rest with a higher brace height.
                          [snip]
                          >The effect you see is not the result of poundage change but rather
                          >distance change. For example, a crossbow braced at 4 inches and drawn 10
                          >inches with a draw weight of 62.5 pounds will yield 625 inch pounds of
                          >pull. If the brace height is raised to 4.4 inches it reduces the draw
                          >length to 9.6 inches. When multiplied against the same 62.5 pound pull
                          >the result is 600 inch pounds.
                          [snip]
                          >If you do actually see the poundage change I would like more information
                          >on the poundages at each brace height, draw lengths, and construction of
                          >the bows.

                          Ok Carolus, simple physics ... and I'm going to use crossbows as an
                          example, just because I find it a better mental model.

                          Ok, Let's say you have a 28" wide crossbow prod, and a 26" long
                          string. That gives you some amount of brace height.

                          Ok, now imagine the crossbow drawn back and cocked. Assume now, that
                          there is a 1" wide nut/shelf/etc it is in.

                          If you measure the length now, of the string on either side of the nut to
                          the tip. You will find it is 12.5" ... half the width of the string, after
                          the 1" of nut is taken into consideration. So the angle the prod is being
                          held at, is to allow for a 12.5" length of string on either side of it to
                          exist. Measure the poundage here.

                          Ok, now, take the string off and twist it tighter until it is only 25" long.

                          Ok, now put it back on the crossbow, and you will have a higher brace
                          height. Agreed?

                          So now, pull back/cock the crossbow. Do the same measurements. Now, there
                          is only 12" on either side of string. By simple physics, the prod has been
                          pulled back farther. There is no other way around it. Now, unless this
                          prod 'somehow' has magical properties that give it a smooth unchanging
                          poundage (I know of none), the fact that it is being stressed farther,
                          means it took more force to get it there, and therefore, if you put a
                          bowscale on it now, the poundage will be higher.

                          Now, as stated, the power stroke is now shorter, as the string stops
                          sooner, and this counteracts 'somewhat' the difference. However, each bow
                          is different, and some stringheight/poundage is the optimum for that
                          bow/prod, others are less efficient, therefore, depending upon the bow, you
                          can adjust it's poundage, and it's power, by playing with that, because in
                          my experience, it isn't a smooth curve.

                          Siegfried
                          (Who will also sit down and do lots of string pulling on one of his
                          crossbows for ya if he has to *grin*)



                          ___________________________________________________________________________
                          THL Siegfried Sebastian Faust http://crossbows.biz/
                          Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                          Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                          http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/



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                        • Scott Jaqua
                          Actually Carolus, as a logic thought problem, I come up with more total stress too. Lower brace height equals a shorter string. A sorter string at the same
                          Message 12 of 24 , Apr 2, 2004
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                            Actually Carolus, as a logic thought problem, I come up with more total
                            stress too. Lower brace height equals a shorter string. A sorter string at
                            the same draw length means the tip of the limb had to flex further. And thus
                            more total stress. But I can't tell you if this is one of the cases where
                            the real world observations don't match theory.

                            Njall
                            (jr rocket scientist, for a real rocket scientist, talk to my dad)

                            Scott B. Jaqua
                            ----------------------------------------------------------------------------
                            -----------------------------
                            The most import right of all, is that of free speech. Without that, all your
                            other rights will soon be taken away. So, I may disagree with what you say,
                            but I will defend until death, your right to say it!
                            ----- Original Message -----
                            From: <eulenhorst@...>
                            To: <SCA-Archery@yahoogroups.com>
                            Sent: Friday, April 02, 2004 2:16 PM
                            Subject: Re: [SCA-Archery] poundage question


                            >
                            > No. The pre-stress is higher but the total stress is identical. A spring
                            tensioned to the same point will only show a certain poundage regardless of
                            the prestress. The archery mechanics site posted earlier has a good
                            discussion of spring loading and prestress under plunger buttons. My
                            results are empirical based on actual tests with a bow scale, not
                            theoretical.
                            >
                            > In Service to the dream
                            > Carolus von Eulenhorst
                            > eulenhorst@...
                            > BTW, that mechanics site has some references on the home page and seems
                            well grounded.
                            > CvE
                            >
                            > -- Siegfried Sebastian Faust <crossbow@...> wrote:
                            > Ok Carolus, I see a slight error here, and I want to try to explain this,
                            > if the explantion doesn't work, I'll draw a graphic ... just let me know.
                            >
                            > I find the
                            > >poundage the same at the same draw length regardless of where I have the
                            > >brace height..The bow is flexed the same amount at the same draw length
                            > >though it is, indeed, flexed more at rest with a higher brace height.
                            > [snip]
                            > >The effect you see is not the result of poundage change but rather
                            > >distance change. For example, a crossbow braced at 4 inches and drawn 10
                            > >inches with a draw weight of 62.5 pounds will yield 625 inch pounds of
                            > >pull. If the brace height is raised to 4.4 inches it reduces the draw
                            > >length to 9.6 inches. When multiplied against the same 62.5 pound pull
                            > >the result is 600 inch pounds.
                            > [snip]
                            > >If you do actually see the poundage change I would like more information
                            > >on the poundages at each brace height, draw lengths, and construction of
                            > >the bows.
                            >
                            > Ok Carolus, simple physics ... and I'm going to use crossbows as an
                            > example, just because I find it a better mental model.
                            >
                            > Ok, Let's say you have a 28" wide crossbow prod, and a 26" long
                            > string. That gives you some amount of brace height.
                            >
                            > Ok, now imagine the crossbow drawn back and cocked. Assume now, that
                            > there is a 1" wide nut/shelf/etc it is in.
                            >
                            > If you measure the length now, of the string on either side of the nut to
                            > the tip. You will find it is 12.5" ... half the width of the string,
                            after
                            > the 1" of nut is taken into consideration. So the angle the prod is being
                            > held at, is to allow for a 12.5" length of string on either side of it to
                            > exist. Measure the poundage here.
                            >
                            > Ok, now, take the string off and twist it tighter until it is only 25"
                            long.
                            >
                            > Ok, now put it back on the crossbow, and you will have a higher brace
                            > height. Agreed?
                            >
                            > So now, pull back/cock the crossbow. Do the same measurements. Now,
                            there
                            > is only 12" on either side of string. By simple physics, the prod has
                            been
                            > pulled back farther. There is no other way around it. Now, unless this
                            > prod 'somehow' has magical properties that give it a smooth unchanging
                            > poundage (I know of none), the fact that it is being stressed farther,
                            > means it took more force to get it there, and therefore, if you put a
                            > bowscale on it now, the poundage will be higher.
                            >
                            > Now, as stated, the power stroke is now shorter, as the string stops
                            > sooner, and this counteracts 'somewhat' the difference. However, each
                            bow
                            > is different, and some stringheight/poundage is the optimum for that
                            > bow/prod, others are less efficient, therefore, depending upon the bow,
                            you
                            > can adjust it's poundage, and it's power, by playing with that, because in
                            > my experience, it isn't a smooth curve.
                            >
                            > Siegfried
                            > (Who will also sit down and do lots of string pulling on one of his
                            > crossbows for ya if he has to *grin*)
                            >
                            >
                            >
                            >
                            ___________________________________________________________________________
                            > THL Siegfried Sebastian Faust
                            http://crossbows.biz/
                            > Barony of Highland Foorde Baronial Web Minister & Archery
                            Marshal
                            > Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target
                            Archery
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                          • eulenhorst@juno.com
                            This only works if the draw distance remains constant thus resulting in more draw with the higher brace height. If the bow is drawn to 28 , for example, it
                            Message 13 of 24 , Apr 2, 2004
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                              This only works if the draw distance remains constant thus resulting in more draw with the higher brace height. If the bow is drawn to 28", for example, it doesn't matter if it started with a brace of 7" or 8". The draw length in the first case is 21" and in the second 20". If, however we use a draw distance of 20" we get a draw length of 27" with a 7" brace and 28" with an 8" brace. In this case the draw weight does change.


                              In Service to the dream
                              Carolus von Eulenhorst
                              eulenhorst@...

                              -- "Scott Jaqua" <jaqua@...> wrote:
                              Actually Carolus, as a logic thought problem, I come up with more total
                              stress too. Lower brace height equals a shorter string. A sorter string at
                              the same draw length means the tip of the limb had to flex further. And thus
                              more total stress. But I can't tell you if this is one of the cases where
                              the real world observations don't match theory.

                              Njall
                              (jr rocket scientist, for a real rocket scientist, talk to my dad)

                              Scott B. Jaqua
                              ----------------------------------------------------------------------------
                              -----------------------------
                              The most import right of all, is that of free speech. Without that, all your
                              other rights will soon be taken away. So, I may disagree with what you say,
                              but I will defend until death, your right to say it!
                              ----- Original Message -----
                              From: <eulenhorst@...>
                              To: <SCA-Archery@yahoogroups.com>
                              Sent: Friday, April 02, 2004 2:16 PM
                              Subject: Re: [SCA-Archery] poundage question


                              >
                              > No. The pre-stress is higher but the total stress is identical. A spring
                              tensioned to the same point will only show a certain poundage regardless of
                              the prestress. The archery mechanics site posted earlier has a good
                              discussion of spring loading and prestress under plunger buttons. My
                              results are empirical based on actual tests with a bow scale, not
                              theoretical.
                              >
                              > In Service to the dream
                              > Carolus von Eulenhorst
                              > eulenhorst@...
                              > BTW, that mechanics site has some references on the home page and seems
                              well grounded.
                              > CvE
                              >
                              > -- Siegfried Sebastian Faust <crossbow@...> wrote:
                              > Ok Carolus, I see a slight error here, and I want to try to explain this,
                              > if the explantion doesn't work, I'll draw a graphic ... just let me know.
                              >
                              > I find the
                              > >poundage the same at the same draw length regardless of where I have the
                              > >brace height..The bow is flexed the same amount at the same draw length
                              > >though it is, indeed, flexed more at rest with a higher brace height.
                              > [snip]
                              > >The effect you see is not the result of poundage change but rather
                              > >distance change. For example, a crossbow braced at 4 inches and drawn 10
                              > >inches with a draw weight of 62.5 pounds will yield 625 inch pounds of
                              > >pull. If the brace height is raised to 4.4 inches it reduces the draw
                              > >length to 9.6 inches. When multiplied against the same 62.5 pound pull
                              > >the result is 600 inch pounds.
                              > [snip]
                              > >If you do actually see the poundage change I would like more information
                              > >on the poundages at each brace height, draw lengths, and construction of
                              > >the bows.
                              >
                              > Ok Carolus, simple physics ... and I'm going to use crossbows as an
                              > example, just because I find it a better mental model.
                              >
                              > Ok, Let's say you have a 28" wide crossbow prod, and a 26" long
                              > string. That gives you some amount of brace height.
                              >
                              > Ok, now imagine the crossbow drawn back and cocked. Assume now, that
                              > there is a 1" wide nut/shelf/etc it is in.
                              >
                              > If you measure the length now, of the string on either side of the nut to
                              > the tip. You will find it is 12.5" ... half the width of the string,
                              after
                              > the 1" of nut is taken into consideration. So the angle the prod is being
                              > held at, is to allow for a 12.5" length of string on either side of it to
                              > exist. Measure the poundage here.
                              >
                              > Ok, now, take the string off and twist it tighter until it is only 25"
                              long.
                              >
                              > Ok, now put it back on the crossbow, and you will have a higher brace
                              > height. Agreed?
                              >
                              > So now, pull back/cock the crossbow. Do the same measurements. Now,
                              there
                              > is only 12" on either side of string. By simple physics, the prod has
                              been
                              > pulled back farther. There is no other way around it. Now, unless this
                              > prod 'somehow' has magical properties that give it a smooth unchanging
                              > poundage (I know of none), the fact that it is being stressed farther,
                              > means it took more force to get it there, and therefore, if you put a
                              > bowscale on it now, the poundage will be higher.
                              >
                              > Now, as stated, the power stroke is now shorter, as the string stops
                              > sooner, and this counteracts 'somewhat' the difference. However, each
                              bow
                              > is different, and some stringheight/poundage is the optimum for that
                              > bow/prod, others are less efficient, therefore, depending upon the bow,
                              you
                              > can adjust it's poundage, and it's power, by playing with that, because in
                              > my experience, it isn't a smooth curve.
                              >
                              > Siegfried
                              > (Who will also sit down and do lots of string pulling on one of his
                              > crossbows for ya if he has to *grin*)
                              >
                              >
                              >
                              >
                              ___________________________________________________________________________
                              > THL Siegfried Sebastian Faust
                              http://crossbows.biz/
                              > Barony of Highland Foorde Baronial Web Minister & Archery
                              Marshal
                              > Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target
                              Archery
                              > http://highland-foorde.atlantia.sca.org/
                              http://archery.atlantia.sca.org/
                              >
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                            • Siegfried Sebastian Faust
                              Hey Carolus ... Sorry for the delay in my reply, been sick. ... The point is, that if you take a bow/prod ... and put a shorter string on it, then pull it back
                              Message 14 of 24 , Apr 8, 2004
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                                Hey Carolus ... Sorry for the delay in my reply, been sick.

                                Anyway ... I think you are missing something:

                                >No. The pre-stress is higher but the total stress is identical. A spring
                                >tensioned to the same point will only show a certain poundage regardless
                                >of the prestress. The archery mechanics site posted earlier has a good
                                >discussion of spring loading and prestress under plunger buttons.

                                The point is, that if you take a bow/prod ... and put a shorter string on
                                it, then pull it back to the same draw length (not power stroke, but draw
                                length) ...

                                Then because of the shorter string, the 'spring' is NOT tensioned to the
                                same point. To get the shorter string to come back to the same spot, it
                                has to pull the 'spring' farther into deflection. Thereby, stressing the
                                material more, thereby, raising the 'poundage' (While very possibly not
                                raising the power because of the shorter power stroke).

                                Again, clear your mind for a second and imagine a crossbow prod with a 3"
                                brace height, and a 28" string on it. Draw it back to a pin, and you will
                                measure 14" of string on either side of the pin. Now take it off and put
                                a 26" string on it. You have your higher brace height.

                                Now, put it back on the same 'jig', and pull it back to the same pin. The
                                prod is now deflected MORE than it was before, because there is only 13" of
                                string on either side of the pin, forcing the prod to bend more to allow
                                for this.

                                Again, if you need it, I'll draw a picture or take a few photos of this in
                                action.

                                > My results are empirical based on actual tests with a bow scale, not
                                > theoretical.

                                As are mine. I can easily put a shorter string on the same prod and have
                                my bowscale read a higher poundage at the same draw.

                                Siegfried



                                ___________________________________________________________________________
                                THL Siegfried Sebastian Faust http://crossbows.biz/
                                Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                                Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                                http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
                              • Siegfried Sebastian Faust
                                ... Exactly ___________________________________________________________________________ THL Siegfried Sebastian Faust
                                Message 15 of 24 , Apr 8, 2004
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                                  At 06:45 PM 4/2/2004, Scott Jaqua wrote:
                                  >Actually Carolus, as a logic thought problem, I come up with more total
                                  >stress too. Lower brace height equals a shorter string. A sorter string at
                                  >the same draw length means the tip of the limb had to flex further. And thus
                                  >more total stress.

                                  Exactly


                                  ___________________________________________________________________________
                                  THL Siegfried Sebastian Faust http://crossbows.biz/
                                  Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                                  Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                                  http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
                                • Siegfried Sebastian Faust
                                  ... No carolus, it does make a difference, the shorter string causes a higher angle of deflection to get to 28 Siegfried
                                  Message 16 of 24 , Apr 8, 2004
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                                    >This only works if the draw distance remains constant thus resulting in
                                    >more draw with the higher brace height. If the bow is drawn to 28", for
                                    >example, it doesn't matter if it started with a brace of 7" or 8". The
                                    >draw length in the first case is 21" and in the second 20". If, however
                                    >we use a draw distance of 20" we get a draw length of 27" with a 7" brace
                                    >and 28" with an 8" brace. In this case the draw weight does change.

                                    No carolus, it does make a difference, the shorter string causes a higher
                                    angle of deflection to get to 28"

                                    Siegfried



                                    ___________________________________________________________________________
                                    THL Siegfried Sebastian Faust http://crossbows.biz/
                                    Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                                    Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                                    http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
                                  • Carolus Eulenhorst
                                    Angles might be slightly different. but poundages have measured the same. There may be some small difference but not enough to read on a scale with 1 pound
                                    Message 17 of 24 , Apr 9, 2004
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                                      Angles might be slightly different. but poundages have measured the same.
                                      There may be some small difference but not enough to read on a scale
                                      with 1 pound resolution. I would still like to see someone else do some
                                      empirical tests on this. Thinking on it while writing this, I might be
                                      able to see some difference on a longbow (all my work was on recurves)
                                      were the rotation of the tips was not a factor.
                                      Carolus

                                      On Thu, 08 Apr 2004 23:25:14 -0400 Siegfried Sebastian Faust
                                      <crossbow@...> writes:
                                      >
                                      > >This only works if the draw distance remains constant thus
                                      > resulting in
                                      > >more draw with the higher brace height. If the bow is drawn to
                                      > 28", for
                                      > >example, it doesn't matter if it started with a brace of 7" or 8".
                                      > The
                                      > >draw length in the first case is 21" and in the second 20". If,
                                      > however
                                      > >we use a draw distance of 20" we get a draw length of 27" with a 7"
                                      > brace
                                      > >and 28" with an 8" brace. In this case the draw weight does
                                      > change.
                                      >
                                      > No carolus, it does make a difference, the shorter string causes a
                                      > higher
                                      > angle of deflection to get to 28"
                                      >
                                      > Siegfried

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                                    • Carolus Eulenhorst
                                      What numbers have you recorded? Carolus On Thu, 08 Apr 2004 23:22:25 -0400 Siegfried Sebastian Faust ...
                                      Message 18 of 24 , Apr 9, 2004
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                                        What numbers have you recorded?
                                        Carolus

                                        On Thu, 08 Apr 2004 23:22:25 -0400 Siegfried Sebastian Faust
                                        <crossbow@...> writes:
                                        > Hey Carolus ... Sorry for the delay in my reply, been sick.
                                        >
                                        > Anyway ... I think you are missing something:
                                        >
                                        > >No. The pre-stress is higher but the total stress is identical. A
                                        > spring
                                        > >tensioned to the same point will only show a certain poundage
                                        > regardless
                                        > >of the prestress. The archery mechanics site posted earlier has a
                                        > good
                                        > >discussion of spring loading and prestress under plunger buttons.
                                        >
                                        > The point is, that if you take a bow/prod ... and put a shorter
                                        > string on
                                        > it, then pull it back to the same draw length (not power stroke, but
                                        > draw
                                        > length) ...
                                        >
                                        > Then because of the shorter string, the 'spring' is NOT tensioned to
                                        > the
                                        > same point. To get the shorter string to come back to the same
                                        > spot, it
                                        > has to pull the 'spring' farther into deflection. Thereby,
                                        > stressing the
                                        > material more, thereby, raising the 'poundage' (While very possibly
                                        > not
                                        > raising the power because of the shorter power stroke).
                                        >
                                        > Again, clear your mind for a second and imagine a crossbow prod with
                                        > a 3"
                                        > brace height, and a 28" string on it. Draw it back to a pin, and
                                        > you will
                                        > measure 14" of string on either side of the pin. Now take it off
                                        > and put
                                        > a 26" string on it. You have your higher brace height.
                                        >
                                        > Now, put it back on the same 'jig', and pull it back to the same
                                        > pin. The
                                        > prod is now deflected MORE than it was before, because there is only
                                        > 13" of
                                        > string on either side of the pin, forcing the prod to bend more to
                                        > allow
                                        > for this.
                                        >
                                        > Again, if you need it, I'll draw a picture or take a few photos of
                                        > this in
                                        > action.
                                        >
                                        > > My results are empirical based on actual tests with a bow scale,
                                        > not
                                        > > theoretical.
                                        >
                                        > As are mine. I can easily put a shorter string on the same prod and
                                        > have
                                        > my bowscale read a higher poundage at the same draw.
                                        >
                                        > Siegfried

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                                      • Carolus Eulenhorst
                                        I just ran this through the calculator with an assumption of 3 being normal brace height and 10 of draw. This changes the angel of deflection by 12 degrees
                                        Message 19 of 24 , Apr 9, 2004
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                                          I just ran this through the calculator with an assumption of 3" being
                                          normal brace height and 10" of draw. This changes the angel of
                                          deflection by 12 degrees or about 15.5% while shortening the power stroke
                                          30% and raising the brace 100% to 6 inches (not taking any rotation of
                                          the tips through prod recurve into account. Realizing that the flexion
                                          of a spring in not a linear curve and the fact that I would be highly
                                          suspect of a bow over braced by this amount, yes, in this case you might
                                          see such a change in poundage. However, in practice I don't find it so.
                                          Of course, I have only been working with brace height changes in the +-
                                          1" range, not the 3" in this case. Extremes do make a difference as
                                          shown in some of the "scientific" studies used to prove political points.

                                          Carolus

                                          On Thu, 08 Apr 2004 23:22:25 -0400 Siegfried Sebastian Faust
                                          <crossbow@...> writes:
                                          > Hey Carolus ... Sorry for the delay in my reply, been sick.
                                          >
                                          > Anyway ... I think you are missing something:
                                          >
                                          > >No. The pre-stress is higher but the total stress is identical. A
                                          > spring
                                          > >tensioned to the same point will only show a certain poundage
                                          > regardless
                                          > >of the prestress. The archery mechanics site posted earlier has a
                                          > good
                                          > >discussion of spring loading and prestress under plunger buttons.
                                          >
                                          > The point is, that if you take a bow/prod ... and put a shorter
                                          > string on
                                          > it, then pull it back to the same draw length (not power stroke, but
                                          > draw
                                          > length) ...
                                          >
                                          > Then because of the shorter string, the 'spring' is NOT tensioned to
                                          > the
                                          > same point. To get the shorter string to come back to the same
                                          > spot, it
                                          > has to pull the 'spring' farther into deflection. Thereby,
                                          > stressing the
                                          > material more, thereby, raising the 'poundage' (While very possibly
                                          > not
                                          > raising the power because of the shorter power stroke).
                                          >
                                          > Again, clear your mind for a second and imagine a crossbow prod with
                                          > a 3"
                                          > brace height, and a 28" string on it. Draw it back to a pin, and
                                          > you will
                                          > measure 14" of string on either side of the pin. Now take it off
                                          > and put
                                          > a 26" string on it. You have your higher brace height.
                                          >
                                          > Now, put it back on the same 'jig', and pull it back to the same
                                          > pin. The
                                          > prod is now deflected MORE than it was before, because there is only
                                          > 13" of
                                          > string on either side of the pin, forcing the prod to bend more to
                                          > allow
                                          > for this.
                                          >
                                          > Again, if you need it, I'll draw a picture or take a few photos of
                                          > this in
                                          > action.
                                          >
                                          > > My results are empirical based on actual tests with a bow scale,
                                          > not
                                          > > theoretical.
                                          >
                                          > As are mine. I can easily put a shorter string on the same prod and
                                          > have
                                          > my bowscale read a higher poundage at the same draw.
                                          >
                                          > Siegfried

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                                        • Bruce R. Gordon
                                          Greetings I approach this discussion with a certain amount of trepidation, since I am definitely not well-versed in the physics of archery or math analysis,
                                          Message 20 of 24 , Apr 9, 2004
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                                            Greetings
                                            I approach this discussion with a certain amount of trepidation,
                                            since I am definitely not well-versed in the physics of archery or math
                                            analysis, but...
                                            On a standard bow, say, a #35 recurve, it is often said; 35 pounds
                                            AT 28 INCHES (emphasis mine). I have always taken this to mean that if
                                            I underdraw the bow, I get less than 35 lbs, and if I overdraw it more
                                            than 28 in., I get a higher poundage. Is this the case, and does it
                                            therefore have relevence to the discussion at hand? Or am I missing
                                            some factor here that would make this not to the point?

                                            Nigel FitzMaurice

                                            > I just ran this through the calculator with an assumption of 3" being
                                            > normal brace height and 10" of draw. This changes the angel of
                                            > deflection by 12 degrees or about 15.5% while shortening the power
                                            stroke
                                            > 30% and raising the brace 100% to 6 inches (not taking any rotation of
                                            > the tips through prod recurve into account. Realizing that the
                                            flexion
                                            > of a spring in not a linear curve and the fact that I would be highly
                                            > suspect of a bow over braced by this amount, yes, in this case you
                                            might
                                            > see such a change in poundage. However, in practice I don't find it
                                            so.
                                            > Of course, I have only been working with brace height changes in the
                                            +-
                                            > 1" range, not the 3" in this case. Extremes do make a difference as
                                            > shown in some of the "scientific" studies used to prove political
                                            points.
                                            >
                                            > Carolus
                                            >
                                            > On Thu, 08 Apr 2004 23:22:25 -0400 Siegfried Sebastian Faust
                                            > <crossbow@...> writes:
                                            > > Hey Carolus ... Sorry for the delay in my reply, been sick.
                                            > >
                                            > > Anyway ... I think you are missing something:
                                            > >
                                            > > >No. The pre-stress is higher but the total stress is identical.
                                            A
                                            > > spring
                                            > > >tensioned to the same point will only show a certain poundage
                                            > > regardless
                                            > > >of the prestress. The archery mechanics site posted earlier has a
                                            > > good
                                            > > >discussion of spring loading and prestress under plunger buttons.
                                            > >
                                            > > The point is, that if you take a bow/prod ... and put a shorter
                                            > > string on
                                            > > it, then pull it back to the same draw length (not power stroke,
                                            but
                                            > > draw
                                            > > length) ...
                                            > >
                                            > > Then because of the shorter string, the 'spring' is NOT tensioned
                                            to
                                            > > the
                                            > > same point. To get the shorter string to come back to the same
                                            > > spot, it
                                            > > has to pull the 'spring' farther into deflection. Thereby,
                                            > > stressing the
                                            > > material more, thereby, raising the 'poundage' (While very
                                            possibly
                                            > > not
                                            > > raising the power because of the shorter power stroke).
                                            > >
                                            > > Again, clear your mind for a second and imagine a crossbow prod
                                            with
                                            > > a 3"
                                            > > brace height, and a 28" string on it. Draw it back to a pin, and
                                            > > you will
                                            > > measure 14" of string on either side of the pin. Now take it off
                                            > > and put
                                            > > a 26" string on it. You have your higher brace height.
                                            > >
                                            > > Now, put it back on the same 'jig', and pull it back to the same
                                            > > pin. The
                                            > > prod is now deflected MORE than it was before, because there is
                                            only
                                            > > 13" of
                                            > > string on either side of the pin, forcing the prod to bend more to
                                            > > allow
                                            > > for this.
                                            > >
                                            > > Again, if you need it, I'll draw a picture or take a few photos of
                                            > > this in
                                            > > action.
                                            > >
                                            > > > My results are empirical based on actual tests with a bow
                                            scale,
                                            > > not
                                            > > > theoretical.
                                            > >
                                            > > As are mine. I can easily put a shorter string on the same prod
                                            and
                                            > > have
                                            > > my bowscale read a higher poundage at the same draw.
                                            > >
                                            > > Siegfried
                                            >
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                                            http://web.raex.com/~obsidian/index.html
                                          • Siegfried Sebastian Faust
                                            ... Tonight, and/or this weekend, I will take a few of my crossbows and do the measurements on them and post it here ... Siegfried
                                            Message 21 of 24 , Apr 9, 2004
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                                              >What numbers have you recorded?

                                              Tonight, and/or this weekend, I will take a few of my crossbows and do the
                                              measurements on them and post it here ...

                                              Siegfried



                                              ___________________________________________________________________________
                                              THL Siegfried Sebastian Faust http://crossbows.biz/
                                              Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                                              Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                                              http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
                                            • Siegfried Sebastian Faust
                                              ... Ok, at least we are riding the same thought train now :) Now that we agree that it can change the poundage ... I agree that all springs are not linear
                                              Message 22 of 24 , Apr 9, 2004
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                                                >I just ran this through the calculator with an assumption of 3" being
                                                >normal brace height and 10" of draw. This changes the angel of
                                                >deflection by 12 degrees or about 15.5% while shortening the power stroke
                                                >30% and raising the brace 100% to 6 inches (not taking any rotation of
                                                >the tips through prod recurve into account. Realizing that the flexion
                                                >of a spring in not a linear curve and the fact that I would be highly
                                                >suspect of a bow over braced by this amount, yes, in this case you might
                                                >see such a change in poundage. However, in practice I don't find it so.
                                                >Of course, I have only been working with brace height changes in the +-
                                                >1" range, not the 3" in this case. Extremes do make a difference as
                                                >shown in some of the "scientific" studies used to prove political points.

                                                Ok, at least we are riding the same thought train now :)

                                                Now that we agree that it 'can' change the poundage ... I agree that all
                                                springs are not linear curves (not even close), and that the difference may
                                                in fact, depending on the prod be unmeasureable, or visible.

                                                In my experience, on at least some of my crossbows, it has been
                                                measureable, as I have measured differences.

                                                Again, this weekend I will grab a couple of crossbows and play.

                                                Siegfried


                                                ___________________________________________________________________________
                                                THL Siegfried Sebastian Faust http://crossbows.biz/
                                                Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                                                Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                                                http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
                                              • Carolus Eulenhorst
                                                Semantics here. might not can depending on construction and design. I haven t seen it on recurve designs, it is not reported by any manufacturer (their
                                                Message 23 of 24 , Apr 9, 2004
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                                                  Semantics here. "might" not "can" depending on construction and
                                                  design. I haven't seen it on recurve designs, it is not reported by any
                                                  manufacturer (their documentation always gives a range of brace heights
                                                  with no reference to poundage change) and only appears relevant when
                                                  taken outside the safe range of variation of a bow. Many changes can
                                                  happen when design specs are exceeded. Please be sure to give all
                                                  relevant measurements with your stats. My tests were with a crossbow
                                                  using a Iolo prod, braced from 3-5" pulled to a nut 14" from the prod.
                                                  Measured a constant 86 pounds.
                                                  Carolus


                                                  On Fri, 09 Apr 2004 09:39:54 -0400 Siegfried Sebastian Faust
                                                  <crossbow@...> writes:
                                                  >
                                                  > >I just ran this through the calculator with an assumption of 3"
                                                  > being
                                                  > >normal brace height and 10" of draw. This changes the angel of
                                                  > >deflection by 12 degrees or about 15.5% while shortening the power
                                                  > stroke
                                                  > >30% and raising the brace 100% to 6 inches (not taking any rotation
                                                  > of
                                                  > >the tips through prod recurve into account. Realizing that the
                                                  > flexion
                                                  > >of a spring in not a linear curve and the fact that I would be
                                                  > highly
                                                  > >suspect of a bow over braced by this amount, yes, in this case you
                                                  > might
                                                  > >see such a change in poundage. However, in practice I don't find
                                                  > it so.
                                                  > >Of course, I have only been working with brace height changes in
                                                  > the +-
                                                  > >1" range, not the 3" in this case. Extremes do make a difference
                                                  > as
                                                  > >shown in some of the "scientific" studies used to prove political
                                                  > points.
                                                  >
                                                  > Ok, at least we are riding the same thought train now :)
                                                  >
                                                  > Now that we agree that it 'can' change the poundage ... I agree that
                                                  > all
                                                  > springs are not linear curves (not even close), and that the
                                                  > difference may
                                                  > in fact, depending on the prod be unmeasureable, or visible.
                                                  >
                                                  > In my experience, on at least some of my crossbows, it has been
                                                  > measureable, as I have measured differences.
                                                  >
                                                  > Again, this weekend I will grab a couple of crossbows and play.
                                                  >
                                                  > Siegfried

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                                                • Siegfried Sebastian Faust
                                                  ... But of course :) And I will be doing it with a Gladius prod, one of my own custom Power-Tuff Fiberglass ones, and maybe something else. I swear I have
                                                  Message 24 of 24 , Apr 9, 2004
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                                                    >Please be sure to give all
                                                    >relevant measurements with your stats. My tests were with a crossbow
                                                    >using a Iolo prod, braced from 3-5" pulled to a nut 14" from the prod.
                                                    >Measured a constant 86 pounds.
                                                    >Carolus

                                                    But of course :)

                                                    And I will be doing it with a Gladius prod, one of my own custom Power-Tuff
                                                    Fiberglass ones, and maybe something else.

                                                    I 'swear' I have seen the differences with these :)

                                                    Siegfried



                                                    ___________________________________________________________________________
                                                    THL Siegfried Sebastian Faust http://crossbows.biz/
                                                    Barony of Highland Foorde Baronial Web Minister & Archery Marshal
                                                    Kingdom of Atlantia Deputy Kingdom Earl Marshal for Target Archery
                                                    http://highland-foorde.atlantia.sca.org/ http://archery.atlantia.sca.org/
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