Scrapers are one of the most misunderstood but useful tools in a woodshop. A scraper in its simplest form is simply a piece of hardened steel that has a small hook on its edge that was created by bending the corner with an even harder rod of steel. But this tool is capable of making tear-out free cuts in hardwoods that no plane (no matter what the price or amount of fettling) is able to manage.
But why do scrapers work? No one seems agree on why, though there are some tantalizing clues from some Japanese micrographs.
How should you sharpen them? On this topic there is even more disagreement. During the last two months I’ve compiled a list of 14 techniques for sharpening this rectangle of steel, and none agrees on the details. Should you file the edge straight, at an angle (what angle?), or perpendicular to the edge. Which kind of file should you use?
Should you stone both the edge and faces of the tool? To what grit? And how should this be done?
Do you have to burnish the faces of the tool before turning the burr of the scraper? If you do, what angle do you use? And how should you burnish the edge to create the hook? At what angle? Do you slide the burnisher along the edge as you turn the burr?
So in true “I have no life” form, I decided to try every one of these techniques and compare the results. I used high-quality scrapers from Lee Valley, Bahco (formerly Sandvick) and Lie-Nielsen. All of the published techniques basically worked and created a tool that makes shavings. Yet some techniques are faster, some are easier for beginners to master and some make a tool that really grabs the work.
And after trying all of these techniques and applying my own training and sharpening experiences to the scraper, I’ve think I’ve found a 15th way to sharpen the tool that doesn’t require a lot of equipment, is faster than any of the other techniques and will result in success the first time you try it.
More experimentation is in order, and I need to see if some other people at work can get the same results as I do. But if the technique does stand up, I think it will make a good article.