Wicked Sharp

Wicked Sharp

For the ultimate edge, use a leather strop.

By Alan Turner

I have a special set of chisels that I only use for paring. To do a good job, they have to be wicked sharp— and stay that way. My secret weapon isn’t a fabulously expensive honing stone. It’s a cheap, homemade strop.

I use these chisels a lot when I’m cutting dovetails (Photo 1). Whenever a chisel feels the least bit dull, I renew its edge on the strop. This only takes a moment, but the results are dramatic. When I pare end grain, for example, I routinely get tissue-thin shavings, not dust. I use the strop quite often, so I store it right next to my chisels (Photo 2).

A strop is a very simple device. It’s just a thick piece of fi rm leather, about 2-3" wide, glued to a block (see Sources, below). The leather is charged with a thin layer of 0.5 micron honing compound (see Sources). A strop will serve you for many years: The leather won’t wear out, and one stick of compound is probably all you’ll ever need to buy.

Here’s how to make one. Cut the leather about 10-12" long, then cut a board slightly wider and longer than the leather. Spread a thin layer of yellow glue onto the board and place the leather on the board (Photo 3). Clamp a second board on top of the leather to keep it fl at. After the glue dries, use your tablesaw to trim the block fl ush with the leather. Next, apply a thin coat of mineral oil to the leather (Photo 4) and rub on some honing compound (Photo 5). Your strop is ready to go.

Before I explain how to use the strop and describe what it does to an edge, let’s return to my set of paring chisels. They’re made of high-quality steel, so they can hold a thin edge. (A chisel with a low angled bevel requires less effort to push when paring than one with a steep-angled bevel.) I grind these chisels at 20°, then hone on 500, 2000 and 8000 grit Shapton waterstones. I don’t use a guide. Instead, I rock the chisel on the stone until I feel both the bevel’s heel and toe contact the surface. Then I start honing, maintaining that angle, until I feel a wire edge on the back of the chisel. I remove the wire edge on the 8000 stone.

Next, I go to the strop. Again, I rock the chisel to find the bevel, press hard, then pull the chisel backwards down the strop. I repeat this process three or four times, making sure I maintain the bevel’s original angle. I also strop the chisel’s back (Photo 6).

What does the strop do? It polishes the edge—making it sharper; and slightly rounds over the edge— making it stronger. I’m convinced that a stropped edge lasts longer than an edge that’s only been honed. It’s amazing!

Click any image to view a larger version.

1. Paring end grain requires an extremely sharp edge. When my chisel feels a bit dull, I go right to the strop to restore its edge.

2. My strop lives on the wall next to my bench, always ready to go. Stropping a chisel takes less than a minute.

3. To make a strop, glue a thick, stiff piece of leather to a block. MDF makes an ideal block—it’s very flat and stable.

4. Prepare the strop by applying a light coat of mineral oil. Work it into the leather—you only have to do this once.

5. Rub honing compound onto the strop. The compound lasts a long time—I only recharge the strop every 3 months or so.

6. Strop the back of your chisel, as well as the bevel. Hold the chisel flat on the strop, so you don’t round the edge, and pull it back.

Sources

Note: Product availability and prices are subject to change.

Tandy Leather Factory, tandyleatherfactory.com, 817-872-3200, Natural Cowhide Leather Strap, 2-1/2" W x 50" L, #4575-00.

Lee Valley, leevalley.com, 800-871-8158, Veritas Honing Compound, #05M08.01.

This story originally appeared in American Woodworker April/May 2011, issue #153.

April/May 2011, issue #153

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