One important life skill for any outdoors person who hunts and fishes is being able to sharpen a knife. There are some nifty rigs out there which can assist in that. However, I would advocate learning how to use just a flat diamond stone. It is relatively simple and not that difficult to master.
Use the 325 mesh face of your DMT diamond stone.
Stroke the knife with the blade at about 11 degrees to the stone surface.
Use equal strokes for either side of the blade.
Continue doing this until the edge of the blade turns.
Change to the 600 mesh DMT diamond stone.
Stroke the knife with the blade at the same 11 degrees to the stone surface.
It will not take many strokes to put a pronounced turn on the blade.
Stroke the knife (more gently) a few times with the blade at about 22 degrees to the stone surface.
Wipe the blade clean and give it a few light strokes on a steel.
Test it for sharpness.
Making a simple angle guide
Fold a piece of paper to make a guide to 22 and 11 degree. Place the folded wedge of paper between the stone surface and the blade. Get a feel for how to stand and the grip required to consistently achieve 22 and 11 degrees. Don’t stress about those angles. While they are pretty much the optimum angle for maximum sharpness, it is not that critical. You will still get a decent result even if you are a bit off with your angle.
How sharp should it be?
A razor sharp edge is not always the best choice for a hunting knife. Professional knifemen talk of a working edge; one that is not razor sharp, but more than sharp enough for the work at hand and one that will hold longer. When you use a razor sharp blade it will tend to turn easily, especially in contact with bone, and will need to be constantly steeled to stand the blade up.
Testing for sharpness
You can test for the turned edge by running your thumb over the blade. You will clearly feel the turn to one, or the other side. Your finger tips are surprisingly sensitive for picking up things like that. Some folks use a short piece of the gal’s stocking, or some other similar light material. Once you have turned the edge, the material will slide off one side, but grip the side with the turn. Once the edge has turned you can complete the final sharpening.
There are a few simple tests for the sharpness of a blade, other than having to tolerate bare patches on your forearms. One is the fingernail test. If you very lightly rest a blade on your fingernail the blade will slide off if not sharp enough. A sharp blade will grip your fingernail.
A test my Dad used to use all the time was to tear off a piece of newspaper and holding it by one corner, gently stroke the blade against the upright unsupported edge. A knife with a good working edge will easily slice off a sliver of paper.
Do Not Do This
One thing I must stress is not to ever put a good blade onto a grinder, sanding disc or any other powered tool. I have seen folks utterly destroy the temper in good knives in a split second.
On a powered abrasive tool the heat build-up in the steel can be extremely rapid, especially on the fine edge. It is quite possible to destroy the temper of the steel in a second! That happens in the blue heat range, way before the red heat glow. There is no remedy for that short of disassembling the knife and getting somebody who knows their business to re-temper and reconstruct it, if that can be done at all.
If you are a newbie, then I suggest you learn sharpening with an old, blunt kitchen knife and not your $3,000 custom blade. Until you develop a feel for the turned edge you can just keep sharpening until it is really pronounced. Once you have a feel for it, you will learn to stop once you have the first indications of turn.
No need to sharpen on the diamond stone
Be aware that after you have been using your sharpened knife, the edge can be easily and quickly rejuvenated by steeling. In most cases, although the knife may appear to be blunt, in fact the edge has just rolled over a little. A few gentle strokes on a steel will stand up the edge nicely and restore the sharpness.
If ever you have stood and watched your local butchers at work you would have noted that they are constantly steeling their knives. A good knife really only needs to be sharpened infrequently, depending on how much work it has done and the type of steel in the blade.