noob mistake - how do i undo my shaving sharp edge safely?

I agree though about the edges that they arrive with. The reason I embarked on this to begin with is one of them has some extra soft metal rolled to one side around the belly and near the cho that I wanted gone and 2 of my Kardas have arrived very dull. I know this is probably for safety but I would like my users to be as sharp as is safe and still strong enough for the blade to work as intended.

Rather than safety, it's likely just that the buffing wheels used to polish the mirror finish on most HI blades buffed the edges dull.... the karda are typically given less attention than the khukuri anyway.
 
My head is going to pop trying to analyze the benefits vs costs on these edge profiles. Since you seem to be quite well educated on the subject, I have a kitchen knife (as I work in a kitchen) that has a crappy edge retention (<56 rockwell if I remember right). I pride myself on having one of the best edges in the house, but the once or twice weekly sharpening on a waterstone is starting to grate on me.

For your sub-par french knife, is the EDC slicer too thin?

The thing about thin kitchen knives is that by keeping the edges thick you actually put more force on the edge, dulling them and deforming them either equally as fast or moreso. With a thin edge of .010-.015" most food (other then things like coconut shells and bones or other hard objects) will give little resistence. The other benefit is that even when dulled, a .010" edge will act sharp, where a .020" edge will act dull. You can see this with really thin box cutters - even through the edge ends up *squared* from use, it still cuts cardboard. This is becasue of it's thinness, the cardboard can give less resistence to the overall geometry so it seperates (albeit with some tearing). Where if you take a 3/16" knife with a .040"+ thick edge, the second it looses it's initial sharpeness it's extremely difficult to cut cardboard, you might not be able to at all if your edge angle is obtuse enough, you'll just end up ripping off chunks or putting all your weight on the knife to get it to go through.

Kitchen knives are very similar. A low hc steel won't be able to maintain it's shape when it's paper thin (.004" like some of the nicer japanese knives), but it will perform better without active sharpening at .010" then it will at .020".

Wow, so it is actually supposed to be "per side" then. I thought that if you wanted a 25 degree edge that you would just aim for a 12.5 degree angle as you sharpened each side.

Thanks.

12.5 degree's per side is what cliff tends to use for his soft wood chopping knives. Personally I don't have good enough technique to keep the edges from deforming quickly, and I prefer to not have to sharpen my knives extensively after each use, though you should always do a light steeling/burnishing/pass on a stone to maintain a crisp initial edge. By getting rid of light dings quickly you have less chance of making them worse as they slam into wood during the next use.

12.5 per side makes for a very thin edge. I'd prefer bringing the edge down to .015" and then putting a 24 degree per side micro bevel on it, because it will create a stronger initial edge but maintain the benefits of a thin overall geometry.
 
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