Producing square mortises is exacting work. The Corner Chisel, used after the mortise has been roughed out by hand or with a slot mortiser—which produces round edged mortises—helps square corners easily and precisely.
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Our Corner Chisel is a modern design based on the larger, more traditional corner chisel or “bruzz,” used extensively in timber framing and other large work. It is a paring tool, useful for trimming mortises and other cuts precisely square. It should not be used to cut directly into solid stock.
Our chisels are ground on four sides, square and parallel. The bevel is flat ground at 30º; additional honing is recommended. On very hard woods, like oak, hard maple or exotic species, take lighter cuts and use a higher secondary bevel.
To sharpen, use a small slipstone with a sharp, square edge of fine India or finer. Slipstones may be trued and squared on 150-grit wet/dry paper or on a glass plate, using medium value grinding compound if necessary. Regrinding is most easily accomplished with a small trued abrasive wheel chucked in a Dremel-type flexible shaft tool. However, a coarse slipstone — with a square, sharp edge — will usually be enough.
We’ve been using Maine grown Hornbeam for many years but, unfortunately, we are no longer able to secure a steady supply. So, we are now offering chisels with Hard Maple handles, which is very tough and a suitable substitute. If we’re able to acquire acceptable Hornbeam in the future, we’ll offer replacement handles in Hornbeam.
When your Chisels arrive, the handles may be loose because of wood shrinkage. They may also loosen during dry weather. The handles are held in place by the wedging of the wood into the tapered socket. Just rap the chisel handle upside down to re-seat the handle. Although we’ve had chisel sets in our shop for years without the handles coming loose, some people have the opposite experience. One solution to a loose handle is to apply hair spray to the tapered section and re-seat as described. Strange as it may sound, it’s effective - and unlike glue, it’s reversible.
One of the advantages of the socket design is that if you want to change handles, you can simply tap the side of the handle on a board and pop the handle off.
To protect your chisels from rust, be sure to oil, wax and/or wrap the tools after use. We recommend Jojoba Oil, a plant based oil product that is non-toxic, odor-free and easy to use. Also, in our shop, we use a fine abrasive handblock to remove any light surface oxide from tool bodies and blades. Jojoba Oil and abrasive handblocks are available from us. Handles are oiled and buffed with wax to produce a natural finish. Wipe with oil as desired to refresh.
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Materials and workmanship are guaranteed for the life of your tool. Call for repairs or replacement parts. We are available for advice if you ever have a problem using your tool.
Sharp chisels are dangerous and should be handled with care. Dull chisels are even more dangerous and should be sharpened.