Cross-wedged handle on a Genova pattern hatchet

FortyTwoBlades

FortyTwoBlades

Baryonyx walkeri
Dealer / Materials Provider
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Mar 8, 2008
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I like using this pattern for rough-shaping work and the factory handle was longer than needed for that task so I whipped this baby up. Hickory with black locust cross wedges. Still a bit of work to do finishing the shape, but it's close enough to be totally comfortable to use as-is now.

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42; I know for sure you didn't whip that up (neither the design nor the shaping) in a 30 minutes. Sound improvisation for a slip fit eye. Your wedging is beautiful.
 
Thanks! The handle design took literally only 5-10 minutes to design, but a few hours to do the rest. I've gotten pretty fast with my digital drafting.

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There are precedents of axe handles with radical forms. I have to think of some Swedish timmerbila which sweep up and away from the line of the cutting edge in particular. Side axes with an off-set also to some degree. These handles are taking advantage of the natural growth of the wood, for example the timmerbila handle will be taken from down low on the tree where the base thickens and there is a natural bend. As it seems the handle of your hatchet is coming from a more or less straight grained wood there is virtually no continuous grain and it seems like a sheer at the shoulder is likely to occur.
 
Although not very "straight", it is straight grained- still continuous wood with no run out. Also, it is heavily built and on a hand hatchet. I would not be overly concerned with breakage.
 
When you extend the line of the back of the handle up and a straight line parallel to that down the front of the eye the area in between these two lined is the area of possible continuity, given a straight grain. Everything outside of these two lines is run-out. Another way of saying there is no continuous grain is to say there is essentially 100% run-out on the handle.You can see on the diagram where he has marked the run-out and your claim of continuous wood with no run-out is a damned stunning one jblyttle. Maybe you could explain. If I were FourtyTwoBlades I would do my best to try breaking that handle and see what happens.
 
Ernest DuBois said:
When you extend the line of the back of the handle up and a straight line parallel to that down the front of the eye the area in between these two lined is the area of possible continuity, given a straight grain. Everything outside of these two lines is run-out. Another way of saying there is no continuous grain is to say there is essentially 100% run-out on the handle.You can see on the diagram where he has marked the run-out and your claim of continuous wood with no run-out is a damned stunning one jblyttle. Maybe you could explain. If I were FourtyTwoBlades I would do my best to try breaking that handle and see what happens.
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See the long-handled one in back? Also made the same way, and used plenty. ;)
(NOTE: the one on it now is a different handle than the one in the video only because I made some adjustments to the design to give it a little more of a swell--the new one has survived a good deal of use, and flexes like a noodle in use.)


Individual wood fibers are actually almost alarmingly short, even in species with the longest sorts, with hickory having a fiber length of only about 1.3mm. While taking advantage of natural curves would be ideal, it's far from necessary.
 
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Shipwrights' adzes have similarly curved handles, as well, and to the best of my knowledge none of them are being steam bent, neither now nor were they historically, at least in factory production. I do pay attention to runout through the neck, but this kind of runout is much more important than the sort resulting from saw-cutting wood along a curve, as it's the bonds between rings that are more likely to separate than within the ring itself.
 
Lastly, I was not "marking the runout" on the diagram, but rather it's a line running from the grip point through the center of gravity of the head, which is how I arrive at these forms. :)
 
Ernest DuBois said:
When you extend the line of the back of the handle up and a straight line parallel to that down the front of the eye the area in between these two lined is the area of possible continuity, given a straight grain. Everything outside of these two lines is run-out. Another way of saying there is no continuous grain is to say there is essentially 100% run-out on the handle.You can see on the diagram where he has marked the run-out and your claim of continuous wood with no run-out is a damned stunning one jblyttle. Maybe you could explain. If I were FourtyTwoBlades I would do my best to try breaking that handle and see what happens.
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It's fairly early on a Monday for me to have stunned anyone, but anything is possible. Perhaps we have a different definition of grain run out, but I don't see any difference between this handle and almost any other typical hatchet handle with straight grain. The curve is pronounced only in relation to the head. If you imagine drawing a straight line from the top back to the bottom front, you will see a fairly straight piece of wood. And it has continuous grain all the way through. Very little if any run-out, at least in the way that I define it. However, this design would lead to horrendous run-out if the grain were turned 90 degrees.
 
jblyttle said:
It's fairly early on a Monday for me to have stunned anyone, but anything is possible. Perhaps we have a different definition of grain run out, but I don't see any difference between this handle and almost any other typical hatchet handle with straight grain. The curve is pronounced only in relation to the head. If you imagine drawing a straight line from the top back to the bottom front, you will see a fairly straight piece of wood. And it has continuous grain all the way through. Very little if any run-out, at least in the way that I define it. However, this design would lead to horrendous run-out if the grain were turned 90 degrees.
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I believe he means runout of the wood fibers rather than growth rings. The rings are continuous through the neck, but if you imagine the fibers in a straight board and then cut a curve through them, you'll be cutting through those chains regardless of the ring orientation. In my experience, with hickory at least, the concern over this has been unfounded. While technically weaker than continuous end-to-end chains following the curves, the elasticity of the wood has been well over that required to withstand the repeated force of use, even when deliberately subjecting it to shock.
 
What’s the “normal” sequence installing cross wedges. Main wedge first,then cross wedges? Cross wedges first? All together?
 
Ah, understood. I honestly had not considered the actual continuous fibers as we are always looking at the growth rings. It does make sense, although in an "ideal versus acceptable" context. The tool in question and it's intended use will go a long way towards determining if this should be a concern or not. While I would avoid serious run-out especially right on the curve of a long striking tool, nothing about that hatchet handle that you created gives me any pause at all.
 
Maine20 said:
What’s the “normal” sequence installing cross wedges. Main wedge first,then cross wedges? Cross wedges first? All together?
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I insert the main wedge first and give it a few blows, then insert the side wedges, knock them in to the same depth, and then drive the rest of the way together.

jblyttle said:
Ah, understood. Still. while I would avoid serious run-out especially right on the curve of a long striking tool, nothing about that hatchet handle that you created gives me any pause at all.
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Yeah, as noted with my little video above, even on a much longer handle it's not been any sort of issue. I've yet to break one of these curved handles.
 
Ernest DuBois said:
When you extend the line of the back of the handle up and a straight line parallel to that down the front of the eye the area in between these two lined is the area of possible continuity, given a straight grain. Everything outside of these two lines is run-out. Another way of saying there is no continuous grain is to say there is essentially 100% run-out on the handle.You can see on the diagram where he has marked the run-out and your claim of continuous wood with no run-out is a damned stunning one jblyttle. Maybe you could explain. If I were FourtyTwoBlades I would do my best to try breaking that handle and see what happens.
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I've long advocated vertical grain with no sideways runout for curved hafts because it's the simplest way to reduce the incidence of sudden and/or catastrophic breaks. Selecting for an inherently curved piece is entirely a labour of love and not remotely practical for the majority of us. Stress on handles increases exponentially with length and hatchet-type handles (such as this carver/shaper/pruner) don't receive anywhere near the strain of implements that are prone to overstrikes and intense leverage. 42 chose a knot-and blem-free piece of wood and oriented the grain optimally. While I'm no fan of 'fanciful (or crazy) curves' on full size axe handles whatever you want to do with a hatchet won't endanger anyone.
 
Run out is where the wood ends. We can hope that for strength and flexibility the wood will continue from end to end without ever being severed but because wood rarely ever goes entirely where we want it, inevitably it does get severed and the best we can do is try and keep as much intact as possible by selecting the wood carefully and being aware that impositions on the wood will in the long run end badly. Here is a piece with run out*. Another way of coming at it using yet more jargon is to say short grain. All of these really imprecise ways of trying to explain the incredible complexity of wood. The condition will not always end in failure and all failures are not because of run out.
It could be I am seeing things and since you are the one to have made the drawing of the handle there FourtyTwoBlades you can set me straight but to my eye there are a series of vague and shadowy squiggly lines at the curves, front and back as well as at the calked end of the grip, no? These are what I was referring to indicating places where the grain is short, the run out. You have clearly cheated in your attempt to test the handle, understandably, ( and I would post in a little yellow smiley-faced character but the option seems to be void just now) all the same why don't you really break it? My money is the break will not be a cross grain fracture but that it will fail along the grain - the short grain.
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Ernest DuBois said:
Run out is where the wood ends. We can hope that for strength and flexibility the wood will continue from end to end without ever being severed but because wood rarely ever goes entirely where we want it, inevitably it does get severed and the best we can do is try and keep as much intact as possible by selecting the wood carefully and being aware that impositions on the wood will in the long run end badly. Here is a piece with run out*. Another way of coming at it using yet more jargon is to say short grain. All of these really imprecise ways of trying to explain the incredible complexity of wood. The condition will not always end in failure and all failures are not because of run out.
It could be I am seeing things and since you are the one to have made the drawing of the handle there FourtyTwoBlades you can set me straight but to my eye there are a series of vague and shadowy squiggly lines at the curves, front and back as well as at the calked end of the grip, no? These are what I was referring to indicating places where the grain is short, the run out. You have clearly cheated in your attempt to test the handle, understandably, ( and I would post in a little yellow smiley-faced character but the option seems to be void just now) all the same why don't you really break it? My money is the break will not be a cross grain fracture but that it will fail along the grain - the short grain.
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I think that many of the lines that you are seeing may be rough marks from rasping.
 
I think it's kind of a theoretical argument on a handle this size.
Between the short length, diameter, and how hard it will be swung I can't see breakage being an issue at all.
Looks nice to use, which was probly the primary goal anyway.
 
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