To me, the tool of choice for sharpening an axe is a simple mill file. I like an 8 or 10 inch file for general work, as it's large enough to get work done quickly, but small enough to be controllable and not get out of hand.
(There is an astounding range of files available, with a variety of shapes and cutting surface patterns. A discussion of files would be at least an article in itself, but Wikipedia gives a great overview.)
With very few exceptions, files only work while being pushed. Pulling a file may damage both your file and the material you're working on.
The edge of my tomahawk is pretty hammered. It leads a hard life and sees quite a bit of use. It's in obvious need of some help, especially with camping season in the very near future.
How to Sharpen Your Axe/Tomahawk/Etc.
- If you have a vise, clamp the head of your axe in it, blade up. This will help you match the original bevel of the edge. If not, you can lay the blade on a workbench or your leg, but be careful.
- Push your file parallel to the existing bevel on your blade, maintaining light, even pressure.
- The main focus while sharpening your axe is to maintain the bevel angle, being sure to avoid rolling the file over the edge as you push.
- On an axe, this is fairly easy. On smaller blades, it is far more difficult, which is why files are not usually recommended for honing those.
- Again, pay close attention to the bevel as you run your stone, and don't roll over the edge.
- As with the file, light, even pressure is what gets the job done.
- You can lay the stone on a flat surface and use it just like you would with a knife, but I prefer to pick it up and run it just like I do the file, as I can see and maintain the bevel more easily that way.
Care for your tools, and they'll care for you for a lifetime.