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Main Boards => PowWow => Topic started by: Dorado on May 17, 2014, 07:50:00 PM

Title: Off balanced bow? Please help.
Post by: Dorado on May 17, 2014, 07:50:00 PM
just got this new (to me) 1958 Bear Polar #60, and I've got a question about it. I haven't had a chance to shoot it yet, draws smooth and feels good, but I've noticed that the upper and lower limbs seem to look out of balance. The upper limb seems to be farther from the string than the lower. I took my bow square and measured it. At peak the upper limb is 8 7/8" away from the string, lower 8 1/4". Is this normal? I know I might be picky but I'm a contractor (and ocd perfectionist) and things like this bug me as they usually mean somethings off. So, is this supposed to be like this or is something wrong? I'll upload pictures for you to see.   (http://i986.photobucket.com/albums/ae347/Dorado1873/Bow/IMG_1143_zpsd4511ad5-1.jpg)
Title: Re: Off balanced bow? Please help.
Post by: Orion on May 17, 2014, 08:19:00 PM
Most production bows will have about 1/4 inch positive tiller, i.e., the top limb will be about 1/4-inch further from the string when measured at the fadeout than the bottom limb. Yours is 5/8 inch positive tiller.  That's out of whack.  Not much you can do about it other than retiller by weakening the bottom limb a little.  It will shoot as it is, but because the limbs are a bit out of tiller, hand shock will probably be a little more. Brace height might also be a bit high.
Title: Re: Off balanced bow? Please help.
Post by: South MS Bowhunter on May 17, 2014, 08:20:00 PM
Stuart,

It is normal for the upper and lower limbs to be anywhere to a 1/16" to 3/8" different based on the tillar of the limbs.  This is measured from the fade out of the upper and lower limbs.

The fade is at the point the riser transitions into the limb core. With your bow scale you would measure at this point and normally for a split finger draw the upper limb would be slightly higher.

You're appears to have more than usual. Maybe someone else will chime in and give there opinion.
Title: Re: Off balanced bow? Please help.
Post by: damascusdave on May 17, 2014, 08:21:00 PM
Someone who understands tiller better than I do will come along and comment...I long ago gave up worrying about such things on old bows...they can be pretty messed up and shoot fine...it just may need some tinkering with the nock point even if the tiller is off

DDave
Title: Re: Off balanced bow? Please help.
Post by: Dorado on May 17, 2014, 08:28:00 PM
QuoteOriginally posted by Orion:
Most production bows will have about 1/4 inch positive tiller, i.e., the top limb will be about 1/4-inch further from the string when measured at the fadeout than the bottom limb. Yours is 5/8 inch positive tiller.  That's out of whack.  Not much you can do about it other than retiller by weakening the bottom limb a little.  It will shoot as it is, but because the limbs are a bit out of tiller, hand shock will probably be a little more. Brace height might also be a bit high.
Brace isn't set, right now it's at about 7" and Min is about 7 1/2" at least that's what I've been told.
Title: Re: Off balanced bow? Please help.
Post by: Jeremy on May 17, 2014, 09:06:00 PM
The tiller on that bow is just fine  :)   Things end up looking a little odd to people who aren't used to the asymmetric limb lengths of the old semi recurves.
I just went and measured 4 of my '57-58 Polars... they are all just north of .5" difference at the fades.  Same for the '54-'56s as well.
The brace for these old bows went by the old 'fistmele' method - 7 to 7-1/2".  I think most of mine are set right in the middle of that (the one I have a low-stretch string on is fantastic to shoot!    :eek:   )
Title: Re: Off balanced bow? Please help.
Post by: damascusdave on May 17, 2014, 10:54:00 PM
Hey Jeremy...good to see you are still around so that when we have a Polar question we know where to go

DDave
Title: Re: Off balanced bow? Please help.
Post by: Dorado on May 18, 2014, 12:17:00 PM
QuoteOriginally posted by Jeremy:
The tiller on that bow is just fine    :)     Things end up looking a little odd to people who aren't used to the asymmetric limb lengths of the old semi recurves.
I just went and measured 4 of my '57-58 Polars... they are all just north of .5" difference at the fades.  Same for the '54-'56s as well.
The brace for these old bows went by the old 'fistmele' method - 7 to 7-1/2".  I think most of mine are set right in the middle of that (the one I have a low-stretch string on is fantastic to shoot!      :eek:     )
This guy right here has made this site worth joining for me.   :clapper:   Thank you so much. I'll be getting the arrows I ordered some time this week and I'll be out back putting the first arrows through it. I can't wait!    :archer2:
Title: Re: Off balanced bow? Please help.
Post by: CoilSpring on May 18, 2014, 03:08:00 PM
Welcome from Alabama - great bunch of folks on this site.