Hi mates,
To me newbie, balance is a vague word. Its really hard to understand. When I shaved down the handle of my M43, I had some observations. I want to share with you guys here so that we can together discuss and learn.
I wrote these words with the Physics knowledge from 9th grade. Dont know whether I am explaining it right. Furthermore, I study my Physics in Vietnamese, my English would sound clumsy. I tried to explain it as best as I could.
Then let me start
In the case of a khukuri, when we chop with a knife, we are trying to shift balance upward and downward. I break it down in 02 phases, upward swing and downward swing.
UPWARD SWING
In upward swing, when we hold the handle, I feel in the point finger area incurs highest pressure. Its where the balance shifts. Then I think the point finger acts as a fulcrum / pivot for the whole knife to lever upward.
From the point finger back to the pommel (the White area), it has a certain weight . With gravity, it creates a downward force called F1. From the point finger to somewhere in the middle of the blade, which I mark it as the Green area, has the same weight as the White area (weight of White area = weight of Green area). Similarly, gravity pulls this Green area and create a force (F2), and F2 = F1. Then both parts balance on our point finger (F2-F1=0).
So there is still the Yellow part left. All the balance we have been talking about lies in here. Its the weight that we can definitely feel when we hold a khukuri. A khukuri is no longer a khukuri without this Yellow part.
When the Yellow area is large, the knife would be head-heavy. The chop would be powerful but the user has difficulty in drawing it back. If the Yellow area is small, then the balance would be too light and create weaker force for the chop.
The balance is perceived differently in different people due to their different strength. This is caused mainly by the Yellow area as well. To me, a suitable weight is about 1/100 of my body weight. I am 63kgs, then a knife of around 630grs will fits me. Dont know if this rule still works on your case.
When we swing it upward, I observed 02 main forces created by wrist and arm+shoulder. The wrist will lift up weight of the Yellow area around the point finger. On top of that, the arm+shoulder, with big muscles, lifts up the weight of the whole knife around elbow and shoulder. This is why we often say an over-weight blade is still okay to chop as long as it has a good balance. The overweight is incurred by the arm, not the wrist, then still enjoyable to use. This case I experienced in my M-43 handle shaving.
DOWNWARD SWING
When we swing the knife downward, the fulcrum / pivot is experienced somewhere around the palm ring. Similarly to Upward swing, there is somewhere in the handle to form a balance of F1=F2, or F1-F2=0, which is the White and Green area.
With the shift of pivot/fulcrum point from point finger to palm ring, the Yellow area extends towards the bolster with more weight, then creates a bigger force for the chop - light lift but powerful chop
This also a point to explain for the function of the palm ring. Sometimes we say with the palm ring, the handle seems to lock into our hands.
In a single chop, I also observe force by wrist, by arms and by shoulder.
Do you guys have any different experience?
To me newbie, balance is a vague word. Its really hard to understand. When I shaved down the handle of my M43, I had some observations. I want to share with you guys here so that we can together discuss and learn.
I wrote these words with the Physics knowledge from 9th grade. Dont know whether I am explaining it right. Furthermore, I study my Physics in Vietnamese, my English would sound clumsy. I tried to explain it as best as I could.
Then let me start
In the case of a khukuri, when we chop with a knife, we are trying to shift balance upward and downward. I break it down in 02 phases, upward swing and downward swing.
UPWARD SWING
In upward swing, when we hold the handle, I feel in the point finger area incurs highest pressure. Its where the balance shifts. Then I think the point finger acts as a fulcrum / pivot for the whole knife to lever upward.
From the point finger back to the pommel (the White area), it has a certain weight . With gravity, it creates a downward force called F1. From the point finger to somewhere in the middle of the blade, which I mark it as the Green area, has the same weight as the White area (weight of White area = weight of Green area). Similarly, gravity pulls this Green area and create a force (F2), and F2 = F1. Then both parts balance on our point finger (F2-F1=0).
So there is still the Yellow part left. All the balance we have been talking about lies in here. Its the weight that we can definitely feel when we hold a khukuri. A khukuri is no longer a khukuri without this Yellow part.
When the Yellow area is large, the knife would be head-heavy. The chop would be powerful but the user has difficulty in drawing it back. If the Yellow area is small, then the balance would be too light and create weaker force for the chop.
The balance is perceived differently in different people due to their different strength. This is caused mainly by the Yellow area as well. To me, a suitable weight is about 1/100 of my body weight. I am 63kgs, then a knife of around 630grs will fits me. Dont know if this rule still works on your case.
When we swing it upward, I observed 02 main forces created by wrist and arm+shoulder. The wrist will lift up weight of the Yellow area around the point finger. On top of that, the arm+shoulder, with big muscles, lifts up the weight of the whole knife around elbow and shoulder. This is why we often say an over-weight blade is still okay to chop as long as it has a good balance. The overweight is incurred by the arm, not the wrist, then still enjoyable to use. This case I experienced in my M-43 handle shaving.
DOWNWARD SWING
When we swing the knife downward, the fulcrum / pivot is experienced somewhere around the palm ring. Similarly to Upward swing, there is somewhere in the handle to form a balance of F1=F2, or F1-F2=0, which is the White and Green area.
With the shift of pivot/fulcrum point from point finger to palm ring, the Yellow area extends towards the bolster with more weight, then creates a bigger force for the chop - light lift but powerful chop
This also a point to explain for the function of the palm ring. Sometimes we say with the palm ring, the handle seems to lock into our hands.
In a single chop, I also observe force by wrist, by arms and by shoulder.
Do you guys have any different experience?
