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The technique of scraping has almost disappeared since the proliferation of power tools and sanding. Scraping has a number of advantages over smoothing with sandpaper, including the ability to take a rough surface which you would normally start sanding with 80 grit paper and producing a smoothness which surpasses that produced by sanding to 220 grit. The shavings made by a properly sharpened scraper look similar to crushed plane shavings, and aren't nearly as messy as that fine sanding dust which is nearly impossible to keep contained. A surface well finished with scrapers shows the grain of fine woods with far more depth and clarity than any amount of sanding could ever produce, since sanding always leaves fine scratches and fills the pores of the wood with dust.
The scraper plane consists of a bench plane body with a forward tilted scraper instead of a cutting iron. This combines the advantages of a plane format, including weight and precise depth of cut, with a scraping cutting action. This tool is especially well suited to smoothing veneers, and leveling figured table tops. See the top of this page for a diagram of how a scraper works.
Adjustment: The scraper blade is sharpened at 60°, then burnished with the burnisher held flat on the bevel, then gradually tilted a few degrees toward the sharp edge. For a mirror smooth finish, sharpen the blade using stones and polish the edge before burnishing. This produces a smooth hook that in turn leaves a smooth surface on the wood. Before setting the blade in the body of the plane, the proper angle of attack must be determined. Push the scraper along a smooth board by hand, starting with the blade held at a right angle, then gradually tilting it forward until the best cutting angle is reached. Holding the blade at this angle, bring the plane alongside and adjust the blade holder as nearly as possible to the same angle. Then, with the plane still on a smooth, flat board, set the blade into the holder, with the cutting edge gently resting on the wood, and lock it in place. This will allow the proper amount of blade to project from the plane. A scraper plane will typically take about .005" of wood per pass, trying to take more may result in chatter marks on the surface.
Use: A scraper plane is used in much the same way a smoothing plane is used. The possibility of chattering may be reduced somewhat by reversing your grip on the plane (so the plane is now facing towards you) and pulling the plane rather than pushing it. This changes the direction of force so that the blade is not forced into the wood deeper than it "wants" to go. Taking passes with the plane skewed slightly also helps. If the blade is cutting too aggressively, the blade can be retracted into the sole by backing off one of the nuts holding the angle of the blade holder no more than a quarter turn, then tightening the opposite nut. As the edge dulls, similar adjustment can be made to keep the blade cutting.
Essentially a small scraper plane with spokeshave style handles, the cabinet scraper is best suited for smaller jobs of the same types as the scraper plane. Sharpening is the same as for the scraper plane. Best results are achieved by pushing the scraper at a skewed angle. See the top of this page for a diagram of how a scraper works.
One of the "lost tools of yesteryear", the chair scraper is the scraping equivalent of the spokeshave. See Woodwork June 1997, pg.51
A hand scraper is simply a flat plate of saw steel. The edge is filed at 90° to the face using a single cut file, then a hardened steel rod called a burnisher is rubbed along the edge to smooth it. The purpose of the burnisher is to mushroom over the edge of the scraper very slightly, making a tiny cutting edge. At first the burnisher is held perpendicular to the face of the scraper, but it may gradually be tilted a few degrees to produce an angled hook, according to the taste of the user. Scrapers come in many shapes, the most common is rectangular, but curved shapes are available to smooth moldings and other curved surfaces, and there are even sets of miniature scrapers for removing burn marks and such from routed profiles. A hand scraper can take .005" or thicker shavings to remove local surface flaws. See the top of this page for a diagram of how a scraper works.
Scratch Stock / Hand Beader:
Before the days of shapers and routers with hundreds of customizable profiles, the only ways to make a molded shape were to buy or make wooden molding planes, or to use a scratch stock. The scratch stock is simply a frame to hold a custom shaped scraper blade in a fixed position and guide it along the board in the desired path (usually parallel to the edge). Skew bladed molding planes, while much more expensive than the lowly scratch stock, have the advantage of cutting more cleanly across the grain, especially in open grained woods.
Burnisher:
A burnisher is simply a rod of steel which is harder than the
scraper. It should be smooth surfaced, and have a suitable cross section
for the shape of the scraper being burnished. In use, the burnisher
is held flat on the edge of the scraper (or flat on the bevel) and rubbed
firmly along the edge. After a few strokes, the handle may be tilted
slightly to form the hook at the desired angle. Shapes of burnishers
include triangular, round, oval, and combinations of all three.
The shavehook is similar in design to a paint scraper, having a straight shank and handle with the blade ground at a 30°-45°. Blade shapes include square, triangular, and teardrop. The blades may be sharpened with a burr, like cabinet scrapers.
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