CWW Card Scraper

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handtool skills

Scrapers are among the lowest-tech tools in the woodshop – right downthere with mallets and two-by-fours. But low-tech or not, these littlepieces of steel can leave a lustrous, tear-free nish on gured hardwood.

The Cabinet ScraperLow-Tech Tool …High Performance Results


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BY BILL PERRY

First: Understand the ToolA card scraper is a small piece of hardened steel with

either a very sharp edge or a small hook on the edge. Ascraper is a cutting tool, just like any other, and needs to

be sharp. A sharp scraper produces fine shavings; a dullscraper makes sawdust. Now here’s the good news: yourscraper responds to sharpening and honing just like anyother blade in your shop. Scraper preparation is a task thatcan drive woodworkers to distraction. Fortunately, thereare just three basics steps and none of them are hard.

Joint and Square the EdgeCard scrapers are rectangles of spring steel or sometimes

they have curved edges for smoothing profiles. Jointing isdone with a fine single-cut file and the scraper held verti-cally in a vise. This needs to be done carefully to achievean even, continuous edge filed at 90˚ to the sides. A guidesuch as the Veritas Jointer/Edger can be helpful to keep thefile at 90˚ or a piece of squared hardwood can be used asa guide. This will produce an edge that is even but it willhave serrations left by the file.

Hone the Jointed EdgeSerrations left by the file must be removed by hon-

ing the jointed edge. A simple way to do this is to lay thestone on top of the workbench, overhanging the edge ofthe bench. Then hold the scraper against the edge of the

bench, using the bench as a guide and slide the scraper back and forth against the bottom of the stone. This tech-nique works well if the thickness of your benchtop is lessthan the width of the scraper. Otherwise the scraper is dif-ficult to grasp.

Note that a scraper will quickly wear a groove in a water -stone. This gives you a couple of options. The first is tohone scrapers only on the edge of the stone. The edge can

be re-flattened quickly, while the faces remain flat andsmooth.

A better option is to use a square block of hardwood tosupport the scraper vertically as the edge is honed againstthe face of the stone. The wooden guide keeps the edgesquare while making it much easier to use the entire faceof the stone without wearing grooves into it. Better yet is touse a diamond bench stone, which wears very slowly due

to its hardness.Now, remember that your best cutting edge will be the

intersection between two finely honed surfaces. Therefore, just as you must hone both the face and the bevel of bladessuch as chisels, you must also hone the two faces of thescraper. This ensures a square, sharp and polished junction

between the scraper’s edge and face.You can hone the face simply by placing the scraper flat

against the stone but this means you’re flattening a bunchof metal that doesn’t need it. Again, like a chisel, the cut-ting edge is what matters, so all you really need to honeis the quarter-inch or so adjacent to the edge. Holding the

Ruler trick it – By supporting one edge of your scraper on a thin steel ruler,you’ll only have to hone a small section of the scraper’s face.

Joint your edges – You must take care to keep the le square to the scraper ifyou are doing this freehand.

Work the steel – Several strokes by the burnisher held at against thescraper’s face work-hardens the metal while forming the beginning of a hook.


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scraper while you do this can be diffi-cult. A rare-earth magnet or a piece ofwood stuck to the scraper with double-sided tape makes it easier.

A slick alternative is to use the “rulertrick” made popular by the British crafts-man, David Charlesworth. When hehones the back of his plane blades, helays a thin ruler down one edge of hiswaterstone, then hones the blade with itsupported by the ruler.

This raises the honing angle by per-haps a degree so that only the cuttingedge contacts the stone, thus minimizingthe amount of metal to be honed. The

small back-bevel that this creates doesn’tseem to affect how a blade cuts but itgreatly reduces honing time. The sametechnique works for scrapers.

Once honed, the scraper is ready forfine work such as finishing, marquetryor final levelling of wood bandings andinlays. For heavier work such as glueremoval or smoothing grain prior to fin-ishing, you will want to burnish a hookonto the scraper’s edge. The amount ofhook depends on the job at hand.

Burnishing the scraperThe hook that you burnish on a

scraper forms the tool’s cutting edge. Tocreate the hook you need a burnishingtool, which is a rod of steel or carbide

harder than the steel used to make thescraper. It spreads the edge of the scraperslightly then rolls that edge over into ahook, creating the edge.

Burnishers are quite inexpensive. Asmall carbide burnisher costs less than$10; the Veritas Tri-Burnisher – a highquality tool suitable for use on rectan -gular as well as curved scrapers – costsabout $30.

Burnishing the face is simplicity itself.Lay the scraper flat on your bench nearthe edge. Make a half dozen passesdown the face with your burnisher (thisis where a longer burnisher excels) withmedium pressure. Turn the scraper endfor end and burnish the face along theother edge, then flip it over and do thesame on the other side. Now you can

burnish a hook. First, secure the scrapervertically in a vise. Holding it betweentwo pieces of flat wood close to theedge may help to prevent it from flex -ing. Next, lightly lubricate the scraper’sedge with a tiny wipe of oil or a bit ofhard wax such as carnauba. Very lit -tle is needed – just enough to reducefriction.

Using light to moderate pressure,draw the burnisher horizontally alongthe scraper’s edge. Two or three strokesshould be enough. This will slightlyspread or mushroom the edge. Howmuch pressure? Well, if you’re hold-ing the burnisher between your thumbs

Heavy hand be gone – Burnishing a hook on a scraper needs only a few light strokes with theburnisher held at an angle of about ve or 10°.


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and index fingers, that’s probably notenough. If you’re leaning over it withthe full weight of your body … you getthe picture. Now repeat the burnish-ing strokes with the burnisher tilted fiveor 10°, first along one side of the edge,then along the other. This will spread themetal further, forming a hook.

Except for heavy scraping work suchas paint removal, very little hook isneeded. With your fingernail, pick at theedge of the scraper. If you can feel thehook, it’s probably large enough. Lightlydrag the hook across your fingernail. Ifit catches the nail and takes a tiny shav-ing, it’s sharp and ready to go.

Since you have two long edges on ascraper blade, you can prepare both thesame way so you don’t have to sharpen

as often. Or, if you wish, burnish aheavier hook on one edge for initialscraping and a very fine hook on theother for finishing. Turn the scraper overand you have four working edges. Aftera bit of trial and error you will get a feelfor how much hook you want for the jobat hand.

Using the scraperFor most work the scraper is held

with both hands, with your thumbs

pushing against the back of the bladeand your fingers holding the front. Thisgrip allows you to bend the scraperslightly, permitting a lighter or heaviercut depending on how much the bladeis bent.

Tilt the scraper forward very slightly – just enough for the hook to slice intothe wood fibres. Bending the bladewill increase the depth of cut. You willfeel this difference, and can adjust itfrom a very fine cut for finishing workto a much heavier cut, such as whenscraping glue squeeze-out from a joint.Super-thin scrapers (as thin as 0.25mm)are also available for the finest finish-ing work. Often effective with just ahoned edge and no hook, these arelight enough to be used one-handed,

either pushed or pulled across a sur-face to remove the last tiny surfaceimperfections.

One caveat about scrapers is that theyare an effective tool for finishing manyhardwoods but are not suitable for soft-woods such as pine, fir, spruce andcedar, or even softer hardwoods such as

basswood, butternut or poplar. A scraperwill simply compress and tear the fibresof these softer woods, instead of shear-ing them off.

SharpeningCurved Scrapers

Some scrapers come with curved edgesso they can be used to smooth concaveor convex profiles. Woodworkers makingreproduction furniture will often cut oldsaw blades into pieces to make scrapersthat are then ground to match the profile

being reproduced.Preparing a curved scraper is slightly

different from one with straight edges.First, you cannot use a flat file to jointthe edge. Use a fine-cut round fileinstead, and then hone the edge using adowel with a piece of abrasive wrappedaround it. This is freehand work, soyou’ll have to be a bit careful to keepyour edges square.

Turning a burr on a curved scraper ismost easily accomplished with a smallcarbide-rod burnisher. Use a stroke asif you were holding a paring knife andpeeling a potato, but instead of cutting,you apply pressure with the burnisher toform the hook.

If you haven’t yet experienced the joys

and efficiency of a card scraper you arereally missing out. This simple piece ofsteel will make easy work out of prepar-ing woods with heavy figure or reversinggrain. Besides, howoften do you get awaywith a $6 woodworkingtool that actually doeswhat it’s supposed to?

Shavings not dust – A properly prepared card scraper will produce gossamer-thin shavings in themost difcult of woods.

Throwing a curve – Burnishing the hookonto a curved scraper is much like using a paringknife to peel a potato.

BILL PERRYwmperry.ca

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CWW Card Scraper