Scraper sharpening

Scraping produces a beautiful smooth surface on wood but a sharp scraper is required.

Sharpening a scraper involves filing the edge flat and smooth and then "rolling" a burr onto the edge using a hardened piece of steel.

Finding the right steel to use as a "roller" can be problematic. I've found an easily available answer to this search.

Take your worn out triangular file and grind off all the teeth (to save your hands). Round the edges to a smooth, dull curve. With the scraper held in a vise, hold the file in both hands and, pressing down firmly, run it along the edge at a slight angle to form a burr.

It's probably possible to use other file shapes in a similar manner but I haven't tried that.

We're talking about BURNISHERS now.
I use round or curved patterns; crochet, onglette, lozenge etc. Far easier to shape and polish. Don't allow heat to draw hardness in grind or polishing. And by polish, a file will take such a smooth finish, like glass. India, Arkansas stones, wet or dry silicon paper backed by a bar work excellently. The microscopic finish needs to run the length of the file, not transverse as the teeth did. Makes essentially a very fine knife sharpening steel, nearly a hone. A hone is fully polished, the sharpener has fine lengthwise 'scratches' that impart a minute cutting action. That will turn the edge of flat, concave, or convex scrapers readily, the 'round' form directs pressure easily, where flat requires somewhat more.
And, if you have swiss pattern jeweler files, the backs of triangular and half-round have that too. Hard enough to burnish heat treated or case hardened surfaces, such a found inside a revolver.