Golly, Jerry, you're embarrassing me, but thank you very kindly. I must say though, that I learned from the best. That would be you, Jerry. Early on, you'd told me the central premise of engraving, which seems obvious, but it's really not: "if you don't have a properly sharpened graver, you won't be able to engrave" and you have to be able to repeat that sharpening result all day long.
Now that's out of the way, let's talk a little about sharpening. Yes, you can make a graver out of a file, a tap, an old endmill, even bog iron if you're willing and able to smelt the iron into a suitable tool steel. And some guys and gals can hold a piece of steel to the grinding wheel, zip, zip, zip, and they have a working graver. Not me. I struggled for years before I took Jerry's class and learned about sharpening with fixtures, and quality tool steel for the graver bits.
The thing about engraving is that you very often will break the tip of the graver. It's part of learning how to cut metal with a chisel. Points break. You simply cannot engrave with a chipped tip, no matter how small the chip is. The graver simply will not cut, or will not stay in the metal, and the graver won't follow your intended line.
With a simple sharpening fixture, Lindsay, for example, you can within a couple of minutes completely restore your cutting point. The GRS multi angle fixture is far more versatile, but complicated. Fixtures are about saving time and repeatability.
Bottom line is, if you're going to get serious about engraving, you will need to spend money on equipment. Hammer and chisel with an Opti-visor is far cheaper than a pneumatic system and microscope. Your tool outlay can range from several hundred dollars investment to ten thousand. Scale your equipment to your wallet and a realistic expectation of how much engraving you will be doing. As you gain experience and skills, you can add to your tool collection.
I recommend for most Kentucky rifle engraving an engraving hammer, chisel, a Lindsay fixture(you need to use 3/32 or 1/8 square tool bits) an Optivisor, and some diamond stones. An in-person engraving class is really almost essential to get you off the ground. It's really hard to learn from books. You will learn some good tips from YouTube videos.