I have an old Camillus that my dad gave to me before he died, and for sentimental reasons, it's all I'll use. The edge had been rounded by years of incorrect sharpening. Using a file, I re-surfaced the edge to where it would fit into one of those inexpensive sharpeners made by Rapala for their filet knives. After resurfacing the edge, I used a Dremel, in stages from sanding discs to polishing grit to restore the area to a luster, then used that filet knife sharpener. That thing is now literally razor sharp, and resharpening is a breeze. A few draws through the course side, then a few through the fine side, and it's shaving sharp.
Just looked it up. It's a pilot survival knife just like the one below.