Groove above the bevel of a Bowie, Name, Purpose and Origin?

Any time you remove material from a solid, it is weakened and becomes less stiff. What you can do is move where the mass in s beams cross section is located to create "a stiffer beam per unit of weight". What this means is you can gave two beams that weigh a pound per foot and one can be stiffer than the other (it will have a higher I value, or Moment of Inertia, which generally means it has more of its mass located father from its centroid or axis of rotation when you look at a cross section). You cannot take a solid chunk of steel beam and cut ANYTHING out of it to make it stiffer.


Bottom line:
A blade can be made wider with a fuller added and be stiffer (in the direction off the edge/spine) than a less wide fuller-less blade that weighs the same amount. The issue here is most blades break perpendicular to the cutting axis (such as when you're prying) and a wider fullered blade has virtually no benefit to strength/stiffness in this direction. It can actually make the blade slightly less stiff in the prying direction....
 
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So I wondered about this today and decided to check the actual affect on the stifness of the blade...
I took two generic profiles of a 2" tall 1/8" thick blade. I added fullers to one (2" diameter, leaving 0.050" blade thickness between the two fullers).
The resulting missing material allowed me to then add a further 0.218" height onto the 2" blade height to give two blade profiles with the same cross-sectional area (only valid where the fuller is present).

I'm too lazy to consult my statics book, but I THINK I remember Moment of Inertia being directly proportional to stiffness...
The results is that for the same cross-sectional area the fuller version has a 41% higher stiffness in the cutting direction and a 16% LOWER stiffness in the prying direction.

 
Good effort Machina, thanks for that :)

- oh, and it was mostly pubs, hotels and restaurants where I did my chef thing back in the day. Mostly in Cardiff then later in Belfast.
 
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