blade hardness question

[kokoek9]

In many of the kukri ads on ebay an edge hardness is given what is a good edge hardness for a kukri

 

[Steve Tall]

From this page
http://www.bladeforums.com/forums/showthread.php/720287-(WiP)-A-kukri-s-quot-working-edges-quot
in the HI Link Library sticky
http://www.bladeforums.com/forums/showthread.php/719860-New-Members-Please-take-time-to-Read-the-Himalayan-Imports-Link-Library

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Section 2 - The Different "Working Edges" of a Kukri:

Blue: the tip and although not as "soft" as people seem to make it sound (probably 52ish HRC), its being directly next to the sweet spot makes it prone to very hard impacts if not handled correctly (hence making it seem "soft" through juxtaposition to the sweet spot). I personally don't make much use of this area except during slicing actions (like if you were to gut an animal, slice up some onions - or perhaps slice the packaging tape to a box containing yet another kukri ). Being the point of the knife, I guess it's also what you'd use for a stabbing action, but I've never found myself needing to use a khuk for such a task.
Green: The "sweet spot" or hardest area (generally ~58-62 HRC) and the only real area you want to use for heavy chopping. Although I sharpen this section to the same level as the others, I tend to increase the angle of sharpening ever so slightly here, making it less prone to deformation during heavy chopping tasks. Obviously since it's the hardest section, you can use it for pretty much any other task you see fit. Also, being the only section of the blade that naturally makes contact with what you're cutting (when perpendicular), you'll end up using this area extensively - especially if you find yourself using your khuk in the kitchen .
Yellow: Belly of the blade and probably 55-57s HRC towards the sweet spot and gradually lessening down to low 50s HRC at the recurve. I use this area for lighter vegetation - from grass up to smaller branches. Since I sharpen this area more acutely than the sweet spot and since it doesn't suffer deformation from hard impacts (impacts that should exclusively be handled by the sweet spot ), it has an easier time slicing through springier objects instead of pushing it away like the sweet spot will tend to do. The overlap into the green area in my diagram just means that I inevitably use that area for these tasks as well (when swiping at a patch of grass for example) but for reasons already stated, the full yellow area is more suited.
Red: The recurved area and relatively soft (probably 50-52 HRC). My #1 use for this area is draw cutting (by gripping the handle of the knife with one hand and the spine towards the tip with the other). Since it's curved and sharpened acutely, it does a great job at stripping bark or shaving wood when used like a draw knife. Again, since it's somewhat softer in this section, assess how hard the bark/wood is before using this section in this manner. I also occasionally grip the kukri by putting my pointer around the cho and my thumb on the spine to use this area as I would a regular knife. Lastly, reverse this grip (thumb on/near cho, fingers on spine) and you're in a great position for peeling fruit (if you have a lighter kukri and/or your wrist and forearm can take it )
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[kokoek9]

Thanks Steve for sharing the information is very helpful. Sharpening has always been a problem your in site helps a lot thanks Mike