"No unnecessary weight in the poll."

[Park Swan]

Gentlemen! All this conjectural BS has got to stop!
42Blades; are those your 'weather-beaten calloused hands' wielding a Baryonyx sharpening puck prototype pictured in another thread?
It's a lot easier to believe advice from folks that have physically used axes a lot than it is to give credence to aficionados that spout the Gospel according to Google.

Do you want to do away with conjecture, or do you want to discredit someone based on a picture of their hand? Those goals are at odds.

 

[FortyTwoBlades]

It's worth noting that this distinctly isn't the "Gospel according to Google" as the only other person I've seen actively write about anything close to this is none other than Dudley Cook. Though he got a lot of things wrong about its significance, he nevertheless observed these dynamics enough to begin gaining an inkling of comprehension of them to the point where he bothered making notes about it. It's just that he draws some false conclusions from it and only scratches the surface of the matter. He called it the axis of lateral pivot, I initially called it the axis of rotational balance, but at this point have settled on the term axle as it's much less of a mouthful while being equally descriptive.

Now, this is all stuff that I would presume any mechanical engineer or physics professor could easily tell you off the cuff, but as far as it being actively described in this context it's something that just hasn't happened other than some observant folks (like G-Pig) instinctively "getting" it and allowing it to influence handle design, etc..

 

[Steve Tall]

The presentation relative to the stroke is dependent on your axle because the axle represents the central axis of mass during the stroke--certain parts will sit forward of it, and some parts rearward of it, and how those parts are oriented relative to that axis impacts how the bit will land.

With an axe the line running through the heel and toe is the bit presentation, and it is oriented relative to the axle. If you were to alter the axle by one mode or another and run it along the same path, it would cause the bit to land at its target differently.

I just want to add that it seems like this would make no significant difference to how the bit lands on the log (for the angle of "presentation"), in actual use, because there are much greater forces involved in swinging and controlling the axe, and the swing is not a simple circular path.

Take the example of bucking a log with a poll-less Tasmanian axe weighing 4 pounds. Add a poll by spot-welding a one pound piece of steel to the back of the head. The center of gravity changes, yes, but the hang is the same and the distance from eye to bit does not change. I would wager that the bit would not act as if it were significantly more "open" or "closed" when it hits the wood.

What I mean by "Hang", "Open" and "Closed":

(Note: I am referring to what has been called the "presentation", not what has been called the "wobble".)

 

[FortyTwoBlades]

Some period writings possibly reference this under the term "line of draught" although it seems to be confused as to whether it means what Square_Peg referred to as the "axis of control" (the axis formed between the two grip points) or the axle formed through the CoG--which is understandable since those English language writings are describing American tools that typically have the two at least very close to one another, making it harder for the observer to distinguish between them unless they had seen examples of strongly off-axis handles before.

 

[FortyTwoBlades]

I just want to add that it seems like this would make no significant difference to how the bit lands on the log (for the angle of "presentation"), in actual use, because there are much greater forces involved in swinging and controlling the axe, and the swing is not a simple circular path.

Take the example of bucking a log with a poll-less Tasmanian axe weighing 4 pounds. Add a poll by spot-welding a one pound piece of steel to the back of the head. The center of gravity changes, yes, but the hang is the same and the distance from eye to bit does not change. I would wager that the bit would not act as if it were significantly more "open" or "closed" when it hits the wood.

What I mean by "Hang", "Open" and "Closed":

(Note: I am referring to what has been called the "presentation", not what has been called the "wobble".)

You're absolutely correct that within a certain range the presentation can be corrected for by altering the stroke. However, it is best to have the axe naturally present itself to the target in the desired way when the user's own natural stroke is used. I actually noted this earlier. The presentation of the bit is altered by axle selection, but then the path which the axe travels to meet the workpiece may be altered in such a way as to cause the axe to still land true.

However, the hang is not the same at that point. The manner shown in the diagram above is a quick-and-dirty rule of thumb approach and the tool would naturally want to present itself further forward in the stroke compared to what it had prior. The distance from the bit to the eye is not what matters so much as the distance from the bit to the axle.

 

[FortyTwoBlades]

These morphs show the influence of altering a number of different variables with the axe and how it impacts all of the other aspects. The dot colors and red line mean the same as before, and the fuchsia line runs through both the heel and toe of the bit to show its presentation.

Remember that the stroke consists of a combination of path and presentation. The rotation of the axe occurs over the length of the path it travels. Alter how much it rotates along that path and the presentation at the time it meets the target will be altered as well.

 

[Square_peg]

Those are my hands, yes. Not sure what you're getting at, but they're plenty calloused. I do pretty much everything around the homestead by hand and I don't wear gloves.

Just to set the record straight, Benjamin is a legitimate daily user of man-powered tools. We have some disagreements on axe and handle geometry but he's for real.

 

[FortyTwoBlades]

And I thank you kindly for those disagreements! There's not many men that can keep a cool head and friendly disposition when debating matters they're passionate about, and yet it's quite important for ideas to be freely exchanged instead of lobbing them at one another like bombshells. I find these exchanges very beneficial in finding what explanations are readily understood and what isn't, and it allows both parties to see what chinks, if any, they can find in their adversaries' arguments. It's what builds strong ideas and understandings. I'd get bored if everyone agreed with me all the time, and it helps push the bounds of collective knowledge forward.

 

[Steve Tall]

...
With an axe the line running through the heel and toe is the bit presentation, and it is oriented relative to the axle. If you were to alter the axle by one mode or another and run it along the same path, it would cause the bit to land at its target differently.

...The presentation of the bit is altered by axle selection, but then the path which the axe travels to meet the workpiece may be altered in such a way as to cause the axe to still land true...

It seems like you're incorrectly considering the "presentation" as simultaneously having two meanings: (1) the angle the bit makes with the "axle" (which depends on the center of gravity), and (2) the angle the bit makes with the target upon landing. Let's use my earlier example (as a "thought experiment") to show that these aren't equivalent, and that the theory is therefore incorrect.

Drill a hole through the knob of that Tasmanian axe handle and mount the 4-pound axe on a fixed shaft that passes through this hole. Arrange it so that the axe can be moved to rotate roughly 180 degrees (around the fixed shaft) before the bit hits the ground. Put a log at the point of impact with the ground. Then measure the "presentation" as the angle the bit makes with the log upon impact.

Now add the 1-pound weight to the poll of the axe. The center of gravity changes, and therefore the "axle" changes, and the angle the bit makes with the "axle" changes. The grip point remains the same (where the shaft passes through the handle), and the swing remains the same (the 180 degree arc), along the same path. Now measure the resulting "presentation" again (the angle the bit makes with the log upon impact). According to your theory, this angle would be different than the previously measured angle. But it seems clear to me that this angle would be exactly the same as the previously measured angle, effectively disproving the theory.

...the tool would naturally want to present itself further forward in the stroke compared to what it had prior...

Are you basing this assertion on anything more than the resting position of the bit when the axe is hung upside down by the knob?

 

[FortyTwoBlades]

It seems like you're incorrectly considering the "presentation" as simultaneously having two meanings: (1) the angle the bit makes with the "axle" (which depends on the center of gravity), and (2) the angle the bit makes with the target upon landing. Let's use my earlier example (as a "thought experiment") to show that these aren't equivalent, and that the theory is therefore incorrect.

Drill a hole through the knob of that Tasmanian axe handle and mount the 4-pound axe on a fixed shaft that passes through this hole. Arrange it so that the axe can be moved to rotate roughly 180 degrees (around the fixed shaft) before the bit hits the ground. Put a log at the point of impact with the ground. Then measure the "presentation" as the angle the bit makes with the log upon impact.

Now add the 1-pound weight to the poll of the axe. The center of gravity changes, and therefore the "axle" changes, and the angle the bit makes with the "axle" changes. The grip point remains the same (where the shaft passes through the handle), and the swing remains the same (the 180 degree arc), along the same path. Now measure the resulting "presentation" again (the angle the bit makes with the log upon impact). According to your theory, this angle would be different than the previously measured angle. But it seems clear to me that this angle would be exactly the same as the previously measured angle, effectively disproving the theory.




Are you basing this assertion on anything more than the resting position of the bit when the axe is hung upside down by the knob?

An error on my part, so good catch--the hang would be the same if the axe were modified in that particular method. :thumbup: Changing the handle length or orientation, extending the bit (not shifting the eye, but actually making the bit longer) or wearing out the toe of the blade would all impact the hang, but not just adding weight to the poll because the bit would still have the same alignment relative to the arc of the pivot in the stroke. That being said, the axle is the central location of your manipulation of the tool, and so the modified axe will arrive at the target sooner, as its edge sits farther ahead of the axle. The angle at which the bit is presented to the target when it lands will be the same as before, but you'll have a shorter distance over which to accelerate it and a longer period of followthrough upon striking the target.

 

[FortyTwoBlades]

Something like this extreme abomination would have the same angle of presentation on impact as the unaltered Council that I diagrammed earlier, but the bit would arrive at the target way sooner. Also you'd have to be the Incredible Hulk to swing it. In all seriousness, though, I've seen some very severe-looking French axes with ultra-long bits and they followed an arc like this, as they should. Can't imagine what they needed it that long for, but I reckon they had their reasons.

 

[Steve Tall]

...That being said, the axle is the central location of your manipulation of the tool, and so the modified axe will arrive at the target sooner, as its edge sits farther ahead of the axle. The angle at which the bit is presented to the target when it lands will be the same as before, but you'll have a shorter distance over which to accelerate it and a longer period of followthrough upon striking the target.

Excuse me? The tool's handle is where it's manipulated. instead of an imaginary line (that you call the "axle"). The modified axe is manipulated by the same physical handle as the unmodified axe, and it travels the exact same path as the unmodified axe, resulting in the same distance over which to accelerate, and the same followthrough (the actual path of the physical axe is the same in both cases, from beginning of acceleration, though the impact).

And I didn't notice an answer to my question about what I see as an underlying flaw in the theory:
"Are you basing this assertion on anything more than the resting position of the bit when the axe is hung upside down by the knob?"

 

[Old Axeman]

42- I got this now. You don't need a poll on your axe because you show the trees your diagrams and talk them to death.
You would have been a big hit in one of my grandfathers logging camps.

 

[FortyTwoBlades]

Excuse me? The tool's handle is where it's manipulated. instead of an imaginary line (that you call the "axle"). The modified axe is manipulated by the same physical handle as the unmodified axe, and it travels the exact same path as the unmodified axe, resulting in the same distance over which to accelerate, and the same followthrough (the actual path of the physical axe is the same in both cases, from beginning of acceleration, though the impact).

And I didn't notice an answer to my question about what I see as an underlying flaw in the theory:
"Are you basing this assertion on anything more than the resting position of the bit when the axe is hung upside down by the knob?"

You're excused. I didn't say that the axle is where it is being manipulated. I said it's the central location of it. It's the hub. The fulcrum. All manipulation of the tool from a single grip point results in motions that originate from the axle. In the case of a triangulated two-point hold it becomes the central plane of manipulation rather than the central axis. The point around which the tool is rotating will always exist somewhere within the plane formed by the grip points and CoG.

Hold the axe right side up by one hand so that it feels like it's standing properly without wanting to topple over. That's the axe upright aligned along an axle. Rapidly twist the axe back and forth, whether rightside up or upside down and you'll see it clearly rotate along a particular axis: the axle. The body has a limited range of motion, and so there are only so many ways that you can hold and swing the axe. If the axe is held either one-handed or with both hands along the axle, and the same stroke as before is used, the bit will land sooner. Again, is there any way you can imagine the extreme example I showed not making it to the target sooner for a given stroke? It does not travel the same distance unless you are starting the axe from the same edge position in space, in which case the axle is starting more rearward, and so while it travels the same number of degrees, the whole stroke is pivoted backwards a bit. Start it with the poll against a blocking "wall"-like barrier and the edge will be sitting nearer the target. Start with the axle in the same place as before, and the edge will be sitting nearer the target.

 

[FortyTwoBlades]

42- I got this now. You don't need a poll on your axe because you show the trees your diagrams and talk them to death.
You would have been a big hit in one of my grandfathers logging camps.

I hoped out loud earlier that you were above this, but clearly I was fated to be disappointed. If you're trying to sting me it's not working, and it's distracting from the debate of the actual concepts. What is your actual argument? Do you have one? From what I can hear, you've loaded your cannon with plenty of powder but forgotten the ball. If you aim to wound, put some material in your debate and point it at my idea. :thumbup:

 

[FortyTwoBlades]

Let's try flipping the script. You guys tell me how an axe balances. What is your definition of a balanced axe? By what means is it made balanced? How do you assess that balance and why do you use that method? What is going on in that method of assessment that makes it work as a means of checking this? How would you balance an "unbalanced" axe without modifying the head? How does an "out of balance" axe behave, and why does it behave that way? What is to be done about it? Where are the forces acting on the axe and how? From where does the axe rotate and pivot?

 

[Hacked]

Let's try flipping the script. You guys tell me how an axe balances. What is your definition of a balanced axe? By what means is it made balanced? How do you assess that balance and why do you use that method? What is going on in that method of assessment that makes it work as a means of checking this? How would you balance an "unbalanced" axe without modifying the head? How does an "out of balance" axe behave, and why does it behave that way? What is to be done about it? Where are the forces acting on the axe and how? From where does the axe rotate and pivot?

Okay so I'm no expert as I'm not a lumber jack and my use of an axe is limited to firewood for my firepit and wood carving projects. I live in a typical suburb so I'm sure that means my opinions are invalid but I'll toss in my two cents since you asked.

To me logically a balanced only really comes into play when chopping on a horizontal axis such as when felling a tree. This is because it in theory would be easier to manipulate the angle at which the bit hits the target. In that situation control over the angle is key for efficiency and safey since the cows mouth and back cut need to be fairly accurate to be successful. An axe that is extremely bit heavy will require more attention and effort to keep on a horizontal plane thus being less efficient.

For bucking, limbing, and splitting a balanced axe is less important. Correct me if I'm wrong but hewing axes are extremely bit heavy but designed specifically to be used on a vertical axis and so the "balance" doesn't really matter. For finer carving I like having a balanced axe as I find it easier to again ajust the angle of the bit to my needs without having to fight the axes natural tendency to aim bit down.

The poll I also see as being designed to maintain the weight of and axe. I don't know if it's just me but I find axes with long bits have a tendency to want to deflect so that the cheek comes down onto the cutting surface. I notice this issue less with my shorter bit axes, though I only really have one axe with a longer bit. You would think that having the weight distributed behind the eye would cause the same effect even with a shorter bit but I haven't found that to be the case. Instead it seems more like the weight drives the bit into the point of contact in a very controlled manner. The point of handles barking the wood in a deeper cut has been mentioned as an advantage of longer bit axes. With my typical American axes I have found that is only an issue when I did not bother to properly slim down the handle. The shoulder should be narrower than the cheeks of the axe head. I've come to perfer taking my handles down to the point were the shoulder is basically non existent and the handle seems to melt into the eye of the axe rather than have an abrupt transition. The effort is worth the results in my experience.

You can sort of see what I mean in this picture. I should note that I tore this handle off after this trip and took the shoulder down further. Pretty happy with it say for the palm swell at this point but I still might carve a new one for the head as it's become an instant favorite of mine.

A note on handles there is a long standing argument on straight verses curved. I find the biggest difference is the slight curve at the end of the handle just before the palm swell. I think part of the purpose of this angle is to help the user control the angle of the bit. By having a curve at that point it makes it easier to tilt the axe head up or down from a horizontal axis without the need for a tight grip. It essentially the difference between using a socket on the end of a straight handled driver vs a ratchet though with a lesser angle. The ratchet is going to require less grip strength to achieve the rotational torque required to turn the bolt than a straight shank driver.

Just my thoughts, nothing scientific.

 

[rjdankert]

. . . the term "line of draught" . . .

This?

Bob

 

[FortyTwoBlades]

This?

Bob

No. I mean with reference to hand tools. I'm not able to find the references at the moment but if I remember correctly they pertained to the age-old debate of straight vs. curved handles. I'm not saying it was a widespread term used to describe the dynamic--merely that a small handful of sources I've seen in the past seem to reference it under that term, although it does seem to be mostly associated with plows, and so may be a borrowed term.

 

[Hacked]

No. I mean with reference to hand tools. I'm not able to find the references at the moment but if I remember correctly they pertained to the age-old debate of straight vs. curved handles. I'm not saying it was a widespread term used to describe the dynamic--merely that a small handful of sources I've seen in the past seem to reference it under that term, although it does seem to be mostly associated with plows, and so may be a borrowed term.

It seems under the American spelling/definition the adjective can refer to (denoting an animal used for pulling heavy loads.
"draft oxen") which would explain the use in discussions about plowing. I'm thinking borrowed term is probably likely.

Going through the expanded definition I also noticed "the action or act of pulling something along, especially a vehicle or farm implement."