Author Topic: Hickory Backing  (Read 1703 times)

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Offline Jedi45

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Hickory Backing
« on: December 11, 2017, 10:12:45 am »
So I got to hasty in my long string tillering and dropped the weight too low. I am bending 27in @ 20lbs and still have work to do.How much weight would a wood backing potentially add? I was thinking of adding a strip of hickory to the back.   

Offline Pat B

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Re: Hickory Backing
« Reply #1 on: December 11, 2017, 12:11:55 pm »
Are you working with a board bow? If not you will have to decrown the back to accept the hickory backing and that alone would drop the weight way more.
 You could probably add 10# to maybe 20# with a hickory backing and adding reflex. What wood are you using for the bow?
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline Jedi45

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Re: Hickory Backing
« Reply #2 on: December 11, 2017, 01:32:10 pm »
It is an ash board bow, which I know isn't ideal but I  have it and need to use it. Its 70in ntn there are a couple runoffs with the grain so it needs to be backed anyway. I have never added reflex before. Does that take a special jig or can you just heat treat and bend it?

Offline JW_Halverson

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Re: Hickory Backing
« Reply #3 on: December 11, 2017, 02:47:26 pm »
Unless you have a genuine 31" draw, you also have room to pike the bow a little shorter, too.

Hickory will be a lot stronger in tension than your ash is in compression, so once you add the backing, be sure to bevel the sides so that the back of the bow is narrower than the belly.  If you were to saw through the limbs bevelled like this, the cross section would not be rectangular, but rather "TRAPEZOIDAL".  This is called "trapping the back".

Now having less surface area of back compared to surface area of belly, you are balancing the forces.  And you must always use the forces, Luke.   Sorry, that slipped out there.

Honestly, though, I would tell you to pike it, go back to early stage tillering and make sure you have zero hinges before tillering it out to whatever weight you then get. Then start afresh. 
Guns have triggers. Bicycles have wheels. Trees and bows have wooden limbs.