Author Topic: Limb physical weight  (Read 1572 times)

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Offline DC

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Limb physical weight
« on: August 17, 2017, 06:43:25 pm »
I'm pretty sure I've asked about this before but I've either forgotten the answer or wasn't entirely sure about the answer. When I mention weight here it's physical weight unless I say otherwise.
  How much does the balance of the physical weight of the limbs matter? I'm re-working a knotty yew bow. When I put it on the tree one side is heavier. The balance point is about 3/4" off center. The tiller is close and I've measured the width every 6" and it's also very close. There are lumps and wide spots for all the knots(about 20 or so) that may be causing the weight difference. Should I width tiller the heavy limb and thickness tiller the other until it sits level on the tree or is it that big a deal? I can't see that having a heavier limb is a good thing but by how much? Do Yumi's physically balance in the hand?

Offline RBLusthaus

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Re: Limb physical weight
« Reply #1 on: August 17, 2017, 07:13:00 pm »
I will start by saying I don't know and I'm sure some wise person be along soon enough.  That said, balancing the tiller is paramount in my mind, not physical weight, as that is what dictates how the bow shoots.  However, I personally don't like a bow that does not balance in he hand, physically, and even if a bow shoots well, I probably would not want it if "it did not feel right"  in my hand. 

The block that my bows sit on on the tiller tree is radiused, helping me balance the bow thru the tiller process.   Sitting on he tree, it should balance in the handle (symmetrical bows).  Put some pull on the string, it now needs to balance via tiller.  Right, wrong or misguided, I can't say, but it is how's my process had developed.  Russ. 

Offline Pat B

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Re: Limb physical weight
« Reply #2 on: August 17, 2017, 07:15:46 pm »
A Yumi is balanced as you draw it but the physical weight of the upper portion is way more than the lower portion but that is because a Yumi bow is tillered like 3 separate limbs I think.
I would think if one limb physically weighed more than the other you would feel more hand shock because the limbs wouldn't recover at the same rate. With the center of the handle being only 3/4" off center I don't imaging it would matter that much plus you could probably get a bit more physical weight off the heavier limb just by narrowing the heavier limb just a bit. You probably wouldn't have to remove much mass to balance it out.
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline gfugal

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Re: Limb physical weight
« Reply #3 on: August 17, 2017, 08:06:31 pm »
Like Pat B said. It might affect hand shock but other than that I can't imagine it affecting it too much, just as long as the tiller is balanced. It would be better to have a balanced tiller vs balanced weight. 
Greg,
No risk, no gain. Expand the mold and try new things.

Offline Marc St Louis

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Re: Limb physical weight
« Reply #4 on: August 17, 2017, 08:17:15 pm »
I don't think I have ever made a bow that balances exactly dead center with equal length limbs but it is usually pretty close.  With a positive tiller then the bottom limb will be stronger and consequently slightly heavier.  If the weight is too far off then you might get some hand-shock but that depends a lot on where that extra weight is located on that heavier limb, if it's in the outer limb then the bow might kick like a Mule
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Offline bradsmith2010

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Re: Limb physical weight
« Reply #5 on: August 17, 2017, 09:11:35 pm »
most the time I hold the bow in my hand,, and when it is balanced,, that is how I shoot it,,
if I am going to put a handle or an arrow rest,,,  I adjust accordly,,
so even if one limb is a bit heavier,, I hold and shoot it at the balance point and that seems to make it a non issue,, (-S

I have one of Marc's bows that I love,, it has not handle or arrow rest,or nocking point,,, I just hold it till it feels balanced and it shoots great,, it is a d bow,, so no way to tell where the limb starts or stops,,

also i will add, if one limb were a bit reflexed it might be lighter cause taking less mass to keep the same bend,,so the bow might not have the same weight limbs,,so just shoot where it is balanced,,

the true test is how the arrow flies,, if you getting nice arrow flight,, then the weight of the limbs is not an issue,, right,,???

Offline Badger

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Re: Limb physical weight
« Reply #6 on: August 17, 2017, 10:08:30 pm »
  The only time I pay any attention to ballance is when I am roughing out a stave. If it is way off I inspect the limbs to see if I screwed up some place. Once a bow is done I check it just for fun, they are always close but seldom exact.

Offline George Tsoukalas

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Re: Limb physical weight
« Reply #7 on: August 18, 2017, 06:58:51 am »
Balancing the physical weight is sometimes a tool in my tool chest but before I begin tillering and not after the bow is done.

What matters to me is, when I draw the bow the handle  pressure is even all the way through the draw. I check that as I bring the bow to full draw.

Jawge
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Offline Bob Barnes

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Re: Limb physical weight
« Reply #8 on: August 18, 2017, 07:02:18 am »
where would be the best 'balance point' to test? 
Seems like common sense isn't very common any more...

Offline George Tsoukalas

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Re: Limb physical weight
« Reply #9 on: August 18, 2017, 07:12:12 am »
Bob, I usually test after floor tiller and from the center.
Jawge
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If you ain't breakin' you ain't makin!

Offline willie

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Re: Limb physical weight
« Reply #10 on: August 18, 2017, 10:51:26 am »
some of the discussions about balance, are about bows for hunting. When carrying a bow in the field, most like the bow to lie level in the hand (or slightly top limb lighter). Its a preference that comes from the desire to not have to look at the bow or make hand placements adjustments prior to shooting. The hunter wants to be able to knock the arrow and raise the bow without taking their eye off the game. I will bet that is why brad sez

Quote
most the time I hold the bow in my hand,, and when it is balanced,, that is how I shoot it,,

of course, having the tiller balanced at that same point is preferable.

Offline bradsmith2010

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Re: Limb physical weight
« Reply #11 on: August 18, 2017, 12:59:24 pm »
yes the tiller needs to be oriented to that balance point,, (AT)