To Split or Cut the Kerf.

DarthTaco123

DarthTaco123

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Mar 28, 2013
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It came up in a few recent topics about the benefit of splitting or cutting a kerf, figured this is fairly pertinent to the forums, and some opinions would be great! As for me I haven't' tried splitting yet, but whenever I cut one it feels like the moment of truth that I'm going to royally bugger up.

Anyways, back to the garage to work on hanging my Sandvik boys axe!
 
I can't think of any reason that splitting would be better.
1. Splitting would be much harder to control the depth and angle.
2. There would be much higher likelihood of the split continuing into/past the shoulder.

That's just my opinion however. I'm sure some guys split a kerf and it works just fine for them.

I've been using a backsaw with good success.
 
i allways split my homemade hafts,and it does fine. just have to leave a few wood to stick out and baton a hatchet that's done.
if it's not too proud and you fear for the hatchet then use a cold chisel (must be a wide one)

compression of the eye avoid to split to the shoulder.
 
Personally I don't see any advantage (but I do see lots of disadvantages) in 'splitting' for a wedge as opposed to cutting of a groove. You have control over the straightness, depth and direction of the kerf when you use a saw and you can mark on the wedge (presuming this too originated from a saw cut) the point at which it will bottom out. With a split you have nothing except for a fervent prayer that the haft fits snug enough not to see the split carry right on through into the haft as the wedge goes in. Folks drill relief holes at the end of glass, steel, fiberglass and iron cracks to keep them from extending further; a saw cut kerf is/does exactly that if the wedge tip is trimmed/blunted to be equal thickness of the kerf cut.
The inventive nostalgia concept of split-generated kerfs and split-generated wedges sounds creative-exotic enough but should not to be considered an improvement. Pioneers, farmers, lumbermen etc, at very least, had some form of handsaw in their kit.
Soviets used a hammer and sickle to glorify their socialist philosophy but north Americans could have crossed an axe and a bucksaw (or better yet a horse-drawn plough) equally well to represent theirs. Wood saws were late-comers in the forestry and forest clearing business because 'live' wood is wholly different from 'dried' wood.
 
Splitting a kerf is physically easier than cutting a kerf by hand. If you don't have a saw handy you can always baton the Axe head you are making a haft for to split your kerf. It is more interesting to look at. I would be willing to bet that a wedge holds better in a split kerf.

Note: I have only split one kerf so keep in mind I am no expert on this subject.
 
300Six said:
Personally I don't see any advantage (but I do see lots of disadvantages) in 'splitting' for a wedge as opposed to cutting of a groove. You have control over the straightness, depth and direction of the kerf when you use a saw and you can mark on the wedge (presuming this too originated from a saw cut) the point at which it will bottom out. With a split you have nothing except for a fervent prayer that the haft fits snug enough not to see the split carry right on through into the haft as the wedge goes in. Folks drill relief holes at the end of glass, steel, fiberglass and iron cracks to keep them from extending further; a saw cut kerf is/does exactly that if the wedge tip is trimmed/blunted to be equal thickness of the kerf cut.
The inventive nostalgia concept of split-generated kerfs and split-generated wedges sounds creative-exotic enough but should not to be considered an improvement. Pioneers, farmers, lumbermen etc, at very least, had some form of handsaw in their kit.
Soviets used a hammer and sickle to glorify their socialist philosophy but north Americans could have crossed an axe and a bucksaw (or better yet a horse-drawn plough) equally well to represent theirs. Wood saws were late-comers in the forestry and forest clearing business because 'live' wood is wholly different from 'dried' wood.
Click to expand...

I agree with this sentiment. A split kerf represents a separation of the wood fibers, and it terminates in a way that can deepen and worsen, potentially causing issues later on. It is inducing weakness in the handle and I would use the method only if I had no other suitable means to haft the axe. A saw-cut kerf has effectively removed material without straining the wood or introducing cracks, and will have a built-in means of preventing over-penetration of the wedge, as mentioned. Splitting is inherently riskier with little gain over sawing.
 
I think splitting might work OK, but only if you have perfect grain alignment within the eye. To make sure the split doesn't progress beyond a certain depth, a small hole (no wider than a saw blade) could be drilled at the stop depth (where the bottom of the saw cut would normally be), through the length of, and in line with the grain.

Easier just to use a saw like it's been done forever.
 
FortyTwoBlades, an built in means of preventing over penetration of the wedge? How does that work?
 
A saw is like a series of tiny chisels. They are cutting material and removing it from the kerf rather than spreading the wood and breaking the bond of the fibers that remain in the workpiece. The means of preventing over-penetration of the wedge is as 300six describes--a flat tip to the wedge corresponding with the flat bottom of the kerf. Once the wedge reaches the bottom of the kerf it is halted and cannot continue.
 
All the commercial axe manufactures that I know of, both USA and off shore cut or saw their kerfs in the handles. If splitting a kerf was a better process, one would think that they would use it as it sure would a easier, cheaper process than cutting a kerf in each handle.

Tom
 
Obviously it's not ideal, but for those few out there who actually use and rely on their axes (which most of us here do not qualify), knowing how to install a handle without a saw is something that is useful. If it's very tight at the bottom, I wouldn't have a terrible amount of trepidation about doing it in a pinch. I've carved dozens and dozens and dozens of handles anyway, and I've sawn all of them, so I am obviously an advocate of that. But there is no reason that a well executed hang can't be done with a split if you know what you are doing.

Be careful though because 42's point about the kerf being a fail safe is only partially true-- a thick wedge can start a split before it even reaches the bottoming out point, if the tongue of the handle is poorly fitted to the eye.
 
Yup--definitely. If the wedge is too thick then you can still split a handle even with a sawed kerf. :)
 
I think that's why the general rule is only cut the kerf 2/3 the depth of the eye. This allows a tight fitting head to prevent possible splitting due to a thick wedge.
 
You can also split or crack the eye and as for a wedge being stopped by the bottom of a sawn kerf, I will definitely call you out on that one FortyTwo.
 
Well, you have to be sensible and not keep mashing it in there after it stops going any further. I'd hope that would be obvious. But it does halt the progress of the wedge from being driven too deep and causing cracking below the head, again providing that you didn't make the wedge too thick in the first place. It is an additional degree of safety provided by a sawed kerf that a split one does not afford.
 
Once again some great discussion however if you think about the bottom of a kerf, the wedge should not be able to be driven that far, it should do its job before that point and never quite reach it. In my experience, if it does, then the wedge should be thicker because either the wedge or the sides of the kerf are compressing enough to allow the wedge to bottom out. That should not be allowed to happen and there is no real advantage in having it bottom out. Sure there is the argument that filling that little void is the ultimate but for the percentage difference it makes to the overall effectiveness or resilience of the axe, it is negligible.
 
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