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hands-on Technique Old and New. The vintage plane on the left was manufactured with a jeweled finish. We duplicated \ the finish on the plane below. Br * vU:- / ▼ Experiment. You can change the look of the jeweling by using different diameters of rods or varying the overlap of the swirls. Not long ago, I came across an interesting old hand plane. It was an infill plane made by Norris, a well-known English plane manufacturer. But the thing that caught my eye was the sides of this plane. They were engraved with what appeared to be a "fishscale" pattern, as in the photo above. The technique used to create this pattern is known as jeweling, engine turning, or spot finishing. It's a process that has been around for decades, and was often used on guns, automobile dash panels, and even on the nose cone of the famed aircraft, The Spirit of St. Louis. Although it looks complicated, the technique is actually fairly straightforward. The pattern is made by "grinding" a series of overlapping swirls on the surface of the metal. And you can do this on a standard drill press. Materials. There are a couple of different ways to create the swirls. One is to mix emery powder or silicon carbide powder with oil to create an abrasive "slurry" that is lightly spread over the surface of the metal. Then a dowel with a piece of leather glued to the end is used in the drill press to grind the pattern into the metal. Another method is to use a rod of rubberized abrasive (commonly known as Cratex). This rubberized abrasive is formed into different diameters of rods. The advantage of this method is that the abrasive is already in the rod, so you don't have to deal with mixing up an abrasive slurry. I used a medium-grit, 3/8"-dia. rod to complete the jeweling on the plane shown in the photo above. (For sources of Cratex rods, see page 51.) Metal Prep. Before you can start grinding the swirls, you need to remove any scratches from the surface of the metal. If you don't, ▼ Materials. Aside from a drill press, all you need for jeweling is a cratex rod. Or you can use some oil and abrasive powder on a wood dowel with a piece of leather glued to the end. Cratex Rod 150-Grit Silicon Carbide Powder Wood Dowel Leather ShopNotes No. 88 |
