Author Topic: loud pop! bamboo backed bow, cracks on belly  (Read 5893 times)

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Offline Hamish

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #15 on: August 12, 2014, 09:05:09 pm »
Whilst those look a lot like chrysals, they look too me like the limb has been twisted side to side( the cause is likely that there is short grain across the belly).Essentially  tension cracks on the side of the limb, rather than a compression fracture.
 You can usually feel chrysals on a braced bow, but not when its unstrung. If its what I suspect you would likely feel the cracks both when braced or unbraced.
Whatever the cause I'm afraid that bow is an accident waiting to happen, don't shoot it.
          Hamish.

Offline Badger

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #16 on: August 13, 2014, 01:01:44 am »
  To me it looks like the bow is very narrow and the belly is very rounded. Thats a good recipe for chrysals.

Online sleek

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #17 on: August 13, 2014, 02:07:44 am »
I agree with Badger. Boo backed osage with a high crown kn the belly focused all the compression forces into a small surface area increasing the pounds of force per square inch by reducing the number of square inches the belly has to disperse the compression. Convex bellies act like a lense and focuse force to its most raised section.

There is a way to mend chrysals without cutting on it but on this bow id say its a lost cause.
Tread softly and carry a bent stick.

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Offline mullet

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #18 on: August 13, 2014, 07:43:35 am »
That's why I asked if the belly was rounded.
Lakeland, Florida
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Online sleek

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #19 on: August 13, 2014, 08:52:17 am »
He certainly hasnt answered many questions directed at helping him has he? It sure looks like a very rounded belly to me.
Tread softly and carry a bent stick.

Dont seek your happiness through the approval of others

gutpile

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #20 on: August 13, 2014, 11:07:51 am »
appears your facets caused the situation...rounding the belly as you did puts all the stress on the center of the osage.....gut

Offline lukelawrence171

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #21 on: August 13, 2014, 01:28:29 pm »
yes, thanks guys the bow does have a very rounded belly i did that because the last bbo i build took alot of set
 I think the main reason for the chrysals  but the grain of the board had alot to do with that there was alot of grain run off in that area of the bow perpendicular to the limbs so some of the grain might have given out in that area. i dont know yet weather ill just sinew rap that area or add a new piece of wood over it, but thanks for the imput guys, I still have alot to learn when it comes to laminated bows

Offline okie64

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Re: loud pop! bamboo backed bow, cracks on belly
« Reply #22 on: August 13, 2014, 02:18:40 pm »
yes, thanks guys the bow does have a very rounded belly i did that because the last bbo i build took alot of set
 I think the main reason for the chrysals  but the grain of the board had alot to do with that there was alot of grain run off in that area of the bow perpendicular to the limbs so some of the grain might have given out in that area. i dont know yet weather ill just sinew rap that area or add a new piece of wood over it, but thanks for the imput guys, I still have alot to learn when it comes to laminated bows

You say you rounded the belly more because your last bbo took too much set ??? Well you  kinda went about that the wrong way. Flatter bellies equal less set. The more round the belly is the less room there is to spread out the compression forces and in turn you get more set. Osage can usually handle a rounded belly but you went a little too round for your grain configuration. If it were mine I would string it up and hang it on a wall somewhere. Chrysals are not worth trying to fix in my opinion.