People seem more concerned about flatten-ing their waterstones, but oilstones also wear, although much more slowly. If you pick up a secondhand oilstone, however, it’s a good idea to check it for flatness and true the sur-face if necessary. Any of the methods for flattening waterstones can be used for oil-stones as well; it’s just going to take a lot longer. Any stone is properly flattened when a straightedge shows an even line of light when laid on edge across the length and width of the surface.
Start by wetting the surface of the plate with water. An inexpensive spray bottle is helpful.
Work the stone evenly over the lapping plate until the surface shows an even texture and color, meaning that it’s true.
Sprinkle the abrasive evenly over the surface of the plate. You don’t need much.
Files
Files are valuable additions to a sharpening kit and essential for making your own cut-ters for beading tools and molding planes.
There are only a few files you really need for sharpening common woodworking tools, but having a wide selection on hand is never a waste of money. It’s hard to own too many.
Metalworking files also come in handy for woodworking.
Rectangular files are the most useful for sharpening scrapers, easing and deburring sharp edges on tools, and other miscella-neous tasks. There are several varieties. Flat files taper in width and are double cut, meaning they have two rows of diagonal teeth. Both edges have a single row of teeth.
Mill files also taper in width but are single cut with one row of teeth. Hand files have parallel sides and a double-cut pattern. They have one safe edge (without teeth) that can ride against an adjacent surface without marring it. A single-cut file cuts more slowly but leaves a better finish than a double-cut file of the same length and grade.
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A collection of files makes a valuable addition to most any work-shop. They have many uses in shaping wood and metal as well as sharpening tools.
Varieties of rectangular files: flat, mill, and hand files.
A safe edge on a file has no teeth.
Single-cut and double-cut files.
A single-cut file leaves a better finish.
Files are further classified by how coarse or fine they are. Bastard is the coarsest, fol-lowed by second cut and smooth. These terms are relative and have to do with the length of the file. A 6-in.-long bastard file is much finer than a 10-in. bastard. For sharp-ening, a second-cut mill file 8 in. or 10 in.
long is a good place to start.
An auger-bit file is handy for many jobs, not just for sharpening auger bits. These small files have safe edges on one end and safe faces on the other, so you can file right up to an inside corner without damaging the adjacent surface. They are about 7 in. long.
Triangular files are used mostly for saw sharpening. Edges form 60-degree angles.
Because an auger-bit file is small and nar-row, it can do a lot more than sharpen auger bits.
From coarse to fine: bastard, second-cut, and smooth files.
An 8-in. or 10-in. second-cut mill file will handle most jobs.
formed corners so the gullet between teeth will be shaped correctly. Many small files made today are not precisely made, so look carefully before you buy.
In addition to these standards, there also are a variety of specialized files. They include feather files, which have very thin edges for sharpening Japanese-saw teeth, and round files, which are used for sharpen-ing chainsaw blades and maksharpen-ing beadsharpen-ing- beading-tool cutters.
Diamond files are good for sharpening, deburring, and honing hardened steel, which regular files won’t cut. They are sold in coarse, medium, fine, and extra-fine grades and are relatively inexpensive.
When any file wears to the point that it no longer cuts well, it is time to get a new Triangular files are single cut, taper in
length, and are classed by length and width:
regular taper, slim taper, extra slim, and dou-ble extra slim.
For fine-tooth saws such as dovetail saws, choose a 4-in. or 5-in. slim taper. File selec-tion for other saws can be made by the size of the sawtooth. When the file is in the tooth, only about one-half of the file should be in the gullet. That way, when one edge begins to dull, you rotate the file to use a fresh edge. But use the smallest file you can.
If the file is too large for the saw, the corner will be too round, or blunt, to file the gullet properly.
When choosing a triangular file for saw filing, check to see that it is straight. Files for fine-tooth saws should have sharp,
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Six-inch triangular files come in several standard sizes, including regular taper, slim taper, extra slim, and double extra slim.
Triangular files are used mainly to sharpen Western saws.
And, unless you’d like to risk getting a hole in your palm, any file with a tang should not be used without a handle, even if the handle is just a length of dowel with a hole drilled in the end. A handle also makes a file easier to use with accuracy.
one. Meanwhile, clean clogged file teeth with a file card. A bit of chalk rubbed in the teeth will help keep soft materials from clogging a file too quickly. Files are very hard (higher than R-65 on the Rockwell scale), so treat them like edge tools and store them carefully, preferably in a rack or tool roll so they won’t bang against one another.
Diamond files are handy for honing hardened-steel tools, especially odd shapes.
Feather files are used to sharpen Japanese saws.
Round files are graded by diameter. They are useful for sharpening chainsaws as well as making custom knives for bead cutters.
A file card is used to clean debris from the teeth of a file.