Primitive Archer

Main Discussion Area => Bows => Topic started by: Grunt on August 27, 2009, 09:36:35 pm

Title: Hic backed cherry compression fracture
Post by: Grunt on August 27, 2009, 09:36:35 pm
After about 75 arrows I noticed the string feeling softer. I held the bow up and there was a hinge started in the top limb about ten inches in. Upon looking close I saw the dreaded chrysalis. I'm thinking that I left the hickory backing strip too thick and it overpowered the cherry belly. I've got another one glued up so should I scrape the hickory to 1/8? 

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Title: Re: Hic backed cherry compression fracture
Post by: Jesse on August 27, 2009, 09:55:23 pm
From what I've seen cherry likes to do that. 
Title: Re: Hic backed cherry compression fracture
Post by: Pat B on August 28, 2009, 12:15:56 am
I've not had much luck with cherry either. It may be best as a core lam or power lam instead of a belly.
Title: Re: Hic backed cherry compression fracture
Post by: sulphur on August 28, 2009, 01:54:30 am
i have made a couple that were durable with a hickory backing.  Yes on the 1/8 thickness.  really it can be even less than that.  cherry is like locust in the way it will chrysal real quick if there is a hinge.  make sure the whole limb is working, go slow while tillering.  also it needs to be at least 1.75" wide and 66" ntn for up 55# of draw weight.  that seemed to work best for mine. 
Title: Re: Hic backed cherry compression fracture
Post by: Ryano on August 28, 2009, 08:52:43 am
Thin your hickory backing to 1/8" and trap the edges. I'd go narrower like 1.5" wide at the most. Its better to keep your core wood a little thicker on a backed bow if possible.
Title: Re: Hic backed cherry compression fracture
Post by: artcher1 on August 28, 2009, 11:09:34 am
As Ryan mentioned, trap the sides on your next on.

Have you thought about repairing the area with a patch Grunt? I just finished a boo back maple bow that done the same thing. The bow started out as a working handle design but I decided to add a handle which overstressed it's original design.  I've salvaged a number of bows that would otherwise be scrapped by using a patch.

ART B

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Title: Re: Hic backed cherry compression fracture
Post by: Grunt on August 28, 2009, 08:23:04 pm
Haven't thought about patching before. I'm going to give it a try as I have nothing to lose. Thanks for the input.