Sharpen A Scraper...And Put It To Work: Turn a hook and watch the shavings fly.Comments (0)
When smoothing wood, I reach for a rectangle of steel called a card
scraper. Despite its humble appearance, a card scraper is remarkably versatile
at refining surfaces. It will remove hardened glue, smooth and level difficult
woods and exposed joints, and smooth a finish. Its small size makes it more
maneuverable than a plane for reaching into tight spots, so you can preserve
your supply of sandpaper. A scraper does it better, faster and without annoying
Scrapers come in all sorts of shapes and sizes, including curved and
profiled. Some can be used in specially designed planes and scraper holders.
But my daily scraper is the card scraper, either thin (0.020-0.025") or
thick (0.30-.0.040") depending on the job at hand. Thinner scrapers excel
at delicate work, where light cuts and finesse are required. Thicker scrapers
are best for heavier work: smoothing tabletops, removing milling marks, and the
like. For most applications, the scraping work is done by a small hook along
the working edge. With a little practice, you can use this tool to produce tiny
shavings, even on hard and figured woods that show tearout when worked with a
Scrapers require sharpening to work
properly, and I’ll show you how this can be done with a few basic tools. You’ll
need a mill file, a block of wood, medium and fine honing stones, and a round
burnisher (a length of polished, hardened steel). For rough work, such as
removing cured glue or cleaning grimy wood, a few strokes on a file will
prepare you for scraping. For finer work, you’ll want to polish the edges to a
mirror shine and then burnish four small hooked edges.
Getting edges straight and square is the
On new or old scrapers, I use a file to establish straight and square edges and to remove any nicks or old burrs. Next, I hone the faces and edges on a 1200-grit waterstone using a simple kerfed block of wood. Then I create a mirror shine by polishing the same surfaces on an 8000-grit stone (similar-grade oilstones work, too), again using the block of wood. Total filing and honing time: About four minutes.
Burnishing creates a tiny hook you can
detect with your finger
The tiny arc of steel on a scraper’s edge, called the hook, is what does all the shaving. Don’t try to maximize the size of the hook–a smaller hook will provide the best performance and a longer-lasting edge. The two steps shown here shouldn’t take more than about 20 seconds, then you’re ready to scrape!
When the hook dulls, you can restore the
hook once or twice by re-burnishing. When you can only produce dust rather than
tiny shavings, it’s time to resharpen.
TIP: If one edge shaves and the opposite edge doesn’t, chances
are the edge wasn’t square before polishing. Make sure the honing block’s kerf
is dead-square to the bottom of the block.
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