Reducing bow poundage
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Reducing bow poundage
However it developed a chrysal about half way up the upper limb which I strapped with superglue soaked nylon thread and covered with epoxy. I have been happily shooting it but it is too heavy for my bad arm. I have never been happy with the finish and I wonder if it would too hard to strip all the layers off and tiller it down a bit. As you can see there are a couple of longitudinal cracks near the handle and riser, but I assume that they don't move much, and also a few pins from spikes.
I love this bow, it is rough but my first Osage one and it took a lot to get there. I think I rushed the finish and now that I am calmer I would like to tweek it down and hopefully reduce any disasters later.
Cheers
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Re: Reducing bow poundage
There would be no issue in stripping the finish off the belly and tillering back to 50 lb. This will also have the effect of reducing the bending stress, which may mean the chrysals will not return (though no promises).
Just treat it once again like a bow that's not yet finished: draw to intended draw weight, observe the tiller, remove wood where it needs to come off, and reassess. Rinse and repeat until your desired draw weight is at your desired draw length.
Just as an aside...the nylon wrapping over the chrysal does nothing but hide it. A chrysal is a little bit of wood that's been pinched up because of the compressive forces parallel to the longitudinal axis of the bow. Wrapping cord tightly around the transverse axis does not reduce the compression, and does not support the belly. But out of sight, out of mind, right?
Just treat it once again like a bow that's not yet finished: draw to intended draw weight, observe the tiller, remove wood where it needs to come off, and reassess. Rinse and repeat until your desired draw weight is at your desired draw length.
Just as an aside...the nylon wrapping over the chrysal does nothing but hide it. A chrysal is a little bit of wood that's been pinched up because of the compressive forces parallel to the longitudinal axis of the bow. Wrapping cord tightly around the transverse axis does not reduce the compression, and does not support the belly. But out of sight, out of mind, right?
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Re: Reducing bow poundage
You are better off getting some new materials and starting a fresh. 60" 70lbs in that design is pretty stressed if its for a 28" draw. Add to that the uncompensated for cluster of knots, in the working area of the limb, its unlikely you will remove the chrysal even if you compensate for the knots an only remove material from every where else, in the reduction to 50lbs.
The bow even if it didn't have a chrysal will still have the string follow of the 70lb bow after the weight reduction.
Sure its possible to do it, but you'll be better served making one 50lbs or so from the start, compensate for any knots, by leaving more wood and or plugging any loose ones.
The bow even if it didn't have a chrysal will still have the string follow of the 70lb bow after the weight reduction.
Sure its possible to do it, but you'll be better served making one 50lbs or so from the start, compensate for any knots, by leaving more wood and or plugging any loose ones.
Re: Reducing bow poundage
I've stripped the back off and reduced the bow to about 55 lb. The chrysal isn't a chrysal but a split . So I am still looking at a fix.
Wait and see.
Wait and see.
Re: Reducing bow poundage
Share a picture or three? If it is a longitudinal split, the fix might be to swill some glue into the crack(s) and clamp them tightly shut.
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Bow making courses, knife making courses, armour making courses and more:
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Articles to start making bows:
http://www.tharwavalleyforge.com/index. ... /tutorials