The Secret to Handscrapers

Sharpening Supplies
A scraper right from a store has no burr. It is in fact just a piece of metal. It becomes a fine tool once you create the burr. The burr is formed in three steps: filing the edge (to flatten it), honing the edge (to draw the steel up) and rolling the burr with a special tool called a burnisher. A burnisher is nothing more than a piece of tool steel — either round, oval or triangular — fitted with a handle. In order to do its job, it has to be harder than the scraper you’re going to burnish and it must be absolutely smooth. I like to polish a new burnisher to a high gloss with a buffing wheel loaded with jeweler’s rouge on the grinder.

Sharpening a Scraper
To create a uniform burr, it’s essential that the edge of a scraper be flat. The easiest way to flatten it is to use a fine mill file held in a simple jig. A half-dozen strokes of the file will get the job done. Next hone the edges perfectly flat. Start by placing the scraper flat on a sharpening stone (along with the proper lubricant) and rub it in a circular motion to remove any burrs created during filing. To hone the thin edge of the scraper, I first sandwich it between two scraps of wood to make sure the scraper is held perfectly perpendicular to the stone. Then holding the sandwiched scraper at an angle on the stone, I rub it back and forth. (Note: If you don’t hold it at an angle, the scraper will cut a groove in your stone.)

Burnishing
Burnishing a scraper is really a two-step process: drawing the edge and rolling the burr. Drawing the edge may seem mysterious at first, but all you’re doing is making it easier to roll a burr. At the same time, you’re hardening the steel so the burr will last longer. To draw the edge, lay the scraper flat on the edge of your bench and draw the burnisher (held at about a 15-degree angle) along its edge. A drop of oil, firm pressure and a handful of strokes will do the job. Repeat this on all four edges.

Next, to roll the burr on each edge, start by clamping the scraper in a vise. Now hold the burnisher at about a 15-degree angle and run it along the edge of the scraper. Firm, steady pressure works best — don’t go overboard here. If you want a fine burr, stop after two or three strokes. Keep going for a heavier burr. Stop often and check the burr by sliding your thumb gently up the face of the scraper and over the edge. With experience, you’ll soon be able to “gauge” the size of the burr.

Using a Scraper
I’ve often seen someone pick up a freshly sharpened scraper and not be able to get a decent shaving. Why? Rolling a burr isn’t an exact science — every time you burnish it the angle changes. This means you have to “find” the best angle to hold the scraper. Quite often, all they have to do to get great shavings is to tilt the scraper one way or the other. It really is trial and error.

Push or Pull?
Ah, the great debate — whether tis’ nobler to push or pull a scraper. My answer: whatever works best for you. I tend to push a scraper because it allows me to get more muscle behind it. For delicate work, I often switch to pulling as I feel it gives me finer control and allows better “feedback” from the wood.

Regardless of whether you decide to push or pull, you’ll have better luck if you flex the scraper. This does a couple things: it keeps the corners from digging into the surface, and it concentrates the scraping action on a smaller section of work. Another trick I often use is to skew the scraper slightly. This prevents it from following uneven surfaces (like planer marks) and quickly levels high points.

Scraping can be hard work, and if you need to remove a lot of material, you’ll find the scraper may get too hot to handle — the friction and heat it creates will quickly spread to your fingers. Although I’ve seen lots of tips on preventing scorched fingers — everything from finger protectors to refrigerator magnets — I offer an alternative. If you have to remove a lot of material, a scraper isn’t the best tool for the job. Set it aside and pull out a hand plane. Once the bulk of the material is removed, generate some of those wispy shavings with your new favorite tool. PW

Rick Peters is a woodworking publishing professional.