Blade sweet spot location

GONESAILING · Jul 18, 1999

While chopping and pruning bushes around the house today, I noticed the best area for chopping on the 20 inch serupati was out just about 7 1/2 inches, close to the last symbol etched in the blade.
On the WW11, it was right at the bend in the cutting edge about 4 inches out.
The center of balance or pivot point is about 3 1/4 inches out on the WW11 and slightly over 4 inches on the serupati.
When I moved the impact out or in, the cutting effeciency changed significantly. The right spot was almost effortless and the experience was like hitting a racket ball pertectly in the web of the racket.
What makes this sweet spot?
Do all khuks have it?
Can it vary in location on different khuks of the same model?
If this has been covered previously, will someone please direct me to the link?

Jim

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What? Another knife? Don't you have enough of those things already?
How many does one person need?

Cliff Stamp · Jul 19, 1999

Gonesailing :

What makes this sweet spot?

Center of mass mainly but blade geometry plays a part as well.

Do all khuks have it?

Everything has it for impact work. A baseball bat has much the same thing.

Can it vary in location on different khuks of the same model?

Yes, but not by much.

Generally start to work at the extreme end near the tip and then switch to the blade right near the handle. Heavy impacts on both these areas will be very uncomfortable and you will quickly get a feel for what you don't want.

Then just start to move towards the middle of the blade. As you hit the right spot vibration and hand slabs will be reduce considerably and you can do full powered chops with little or no ill effects.

It is much easier to find it with a little work than to try and calculate it. Probably a good deal more enjoyable to most as well.

-Cliff

Bill Martino · Jul 19, 1999

Thanks, Cliff. Experimentation should tell you which part of the blade is the right spot after maybe five minutes of chopping. It does not take long.

Uncle Bill

GONESAILING · Jul 19, 1999

Thank you Cliff
I guess I need to look up center of mass vrs balance point.
I have a CS recon scout that needs to have its sweet sopt identified

. It will be interesting to see what effect the curvature of the khuks have as opposed to the straight blade.
How do you get those neat quote functions??
Jim

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What? Another knife? Don't you have enough of those things already?
How many does one person need?

Cliff Stamp · Jul 20, 1999

Jim, to get quotes (and other things) just click on the UBB link that you see when you post. It should be to the left of the box that you type your post in.

The Recon Scout is a nice little knife, blade heavy, the one I have is balanced 1 cm in front of the guard.

-Cliff

Bill Martino · Jul 20, 1999

Gone, you may not be aware of this but Cliff is a Phd candidate in physics -- just in case you are wondering why he knows so much about center of gravity, mass, force, etc.

Uncle Bill

GONESAILING · Jul 20, 1999

Cliff

Jim, to get quotes (and other things) just click on the UBB link that you see when you post. It should be to the left of the box that you type your post in.

Just trying out the UBB function

ghostsix · Jul 20, 1999

I`d like to read his dissertation.

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Bill Martino · Jul 21, 1999

As a matter of fact, so would I -- if it is not to academic.

Uncle Bill

ghostsix · Jul 21, 1999

It won`t be;knowing Cliff.Few of them are ever read except by the board.They dissappear into academia.In most cases,rightly so.There is the ocassional exception,but they are rare.He might drive me to the dictionary or a Proffessor.I do have assets available with a phone call.I suspect that he would be actually trying to say something.

mohd · Jul 21, 1999

Testing ...

to get quotes (and other things) just click on the UBB link

Cliff - thanks for the trick !

Sweet spot ? I think it varies depending on the type of work you do - meaning the sweet spot for chopping log is at one place, the sweet spot for cutting tree is at another place, the sweet spot for slicing potato is again at another part and the sweet spot for peeling apple is also at another area.

GONESAILING · Jul 21, 1999

Sweet spot ? I think it varies depending on the type of work you do.

Thanks for suggestions.
The balance point on each blade was close to the same measurement, however the sweet spot was much foward on the serupati.
Are you saying that the way you use it, like what kind of arm swing, grip, or even force can change the spot??
Would arm length also have any effect?
It is obvious that I am not a PhD candidate.
Can't even play one on TV!!

To me it seems that these khukuris may have properties and designs that we in the last of the 20th century, simply haven't discovered.
Oh the sweet mysteries of life.
Jim

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What? Another knife? Don't you have enough of those things already?
How many does one person need?