Are opinels 12C27? I couldn't find anywhere that mentions the grade on their site. It just talks about Stainless and carbon steels in general. Not disputing the claim, just interested. My Morakniv is the same it just says its stainless but I can't see what grade, but it is very sharp.
My Boker penknife has 12C27 and it's razor sharp. Granted 12C27 is a mid range steel from what I've read, so can't expect too much, but more than your bog standard penknife jobbie.
I have wondered about making my own handle for an opinel as they are easy to diy.
As I understand it, there are different geometries used to make knife (and axe) edges, depending on their intended use. For carving purposes, a scandi edge (two flat bevels) is preferred over a convex-bevel edge.
The convex bevel edge is stronger and good for knives that are used for bushcraft purposes - splitting and hacking-mightily at stuff, perhaps involving hitting the back of the knife blade with a branch-mallet to drive the edge into something. The scandi grind gives an edge that's a bit more "delicate" but the flat bevel makes it easier to carve with when various convex and concave surfaces are being formed, as with spoons and similar, with very fine and controlled cuts.
Some use a concave bevel for carving knives but that can make the already very thin arris of a carving knife even more delicate. Some commercially made carving knives - Beavercraft is one - do come with concave bevels but as these are honed over use and time the very small concavity becomes flattened into a scandi.
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No doubt there are knife users who can perform any operation with any kind of steel, edge geometry and sharpness. No doubt one could carve a spoon with a flint knife or even grind one into shape with a lump of sandstone, after enough practice and effort. But different steels, configurations and degrees of sharpness can improve the making process, in terms of ease, type/precision of cuts possible, time/work before the edge degrades and so forth. All those nuances are worth knowing and practicing.
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The various knifey folk out in webland generally promote carbon steel knives as better than stainless steel knives if sharpness is the prime requirement. Stainless is better for bushcraft uses basically because those uses don't need such a high degree of sharpness and stainless doesn't rust like carbon steels in damp environments. Most mass-makers of knives do both.
Morakniv do one that has a layered-blade, with a very hard central carbon steel layer to take the very sharp & resilient edge, clasped by two softer layers to keep the harder layer from fracturing or breaking.
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I've used various carving knives for making spoons, bowl and so forth from green wood over the past 14 months. I've made over 100 items so far, from various kinds of green wood, using various knives. My own experience is that some knife steels and edge/bevel configurations make a significant and easily noticeable difference to the ability of the knife to make easy/clean cuts and to stay sharp or go back to sharpness easily. The differences are real and do make a difference to the quality of one's experience when carving with them. It soon becomes a preference to avoid poorly made penknives of inadequate steels and edge profile in favour of better designed and made items oriented at a specific kind of use.
