Consistency equals accuracy! The reason may be that you change from one method to another that has a completely different approach. Try to stick with one method until you know all the caviats and can adapt.
^^That's the ticket. :thumbup:
Part of really learning to sharpen is owning the responsibility to do what it takes to get there. That means practice, practice and practice some more. Not enough knives? Buy or find some more inexpensive knives (garage sales, flea markets, auction sites, etc) and go from there. Look for old knives in simple carbon (non-stainless) steel; they're usually more consistent and will usually reward a good effort with a screaming-sharp edge. That's not to say you shouldn't also work with stainless blades, as you'll see WIDE variability in how each of those sharpens up; that's part of the process of learning as well, and in figuring out which tools, abrasives or methods work best with a given steel, and you'll also learn to spot both the really good blades (fine grain, good heat treat), and the horrible ones that'll never take or hold a decent edge, due to impure processing or bad heat treat.
Even after you've worked a long while with one tool and think you've 'figured it all out' with that one, put it away for a while (weeks, maybe months) and work with something different, then go back later and re-visit what you think you knew about the previous method. You'll likely be surprised at how much better you'll be with it, as learning new methods and tools usually pays off across the board, even with methods or tools you thought 'didn't work' before, or at least those you thought were difficult then, but not now.
The 'practice, practice, practice' aspect is what develops consistency with the hands, in maintaining and holding the right angle, making the best use of pressure, developing fluidity and repeatability of motion in your stroke, and developing the 'feel' for finding flush bevel contact on the hones and other tools used. That's the core of real sharpening skill, and is what will make all of the tools you try out much simpler and more consistent in use.
AND, be willing to recognize and accept that there'll always be some 'off days' in sharpening, when 'the touch' just seems to abandon your hands completely. Don't sweat it though; just accept that it'll be back in due time, because it will be.
David
