Pattern Routing Curved Shapes
Looking for some help pattern routing curved shapes? Here’s a quick way to do it based on a wall-mounted dining server project by former Popular Woodworking publisher Steve Shanesy. The full project – as well as other great simple yet elegant furniture builds – also appears in the book “Contemporary Furniture: 17 Projects You Can Build,” now available from Popular Woodworking Books.
Except for the back edge, my dining server design has no straight lines. The front edge is a sweeping curve, the ends are a more subtle curve and the corners have a large bend to join the two. This design mirrors one edge of my dining table, so I simply used that portion of the table pattern to shape the server.
How are these fair curves generated? Pattern routing the curves is a great solution – here’s how. On a large sheet of craft paper, I found the curve I wanted for the table’s long edges by bending a narrow strip of 3⁄8″-thick plywood between fixed points. With my bending stick set to a pleasing curve, I transferred the shape to my paper.
To determine the corner radius I used trammel points and, by trial and error, found a radius that looked nice to my eye, then blended the lines into one seamless curve. Then I carefully cut the shape from the craft paper.
To make the top template, I used a piece of 1⁄4″-thick MDF. (The template needs only to be slightly more than half the server’s length.) I taped the paper to the MDF then traced the outline as shown at left above. I also marked the centers of the front and ends; these centerlines are important for aligning the template when moving it from one section of the top to the other.
Next, I used a jigsaw to cut the MDF at the pencil line. I took my time, knowing that any irregularities required block-sanding the edge to fair the curve. (Imperfections in the template will transfer to your finished work because the router bit bearing rides on the pattern to guide the cut.)
To use the template, align the centerlines of the template with your workpiece then transfer the shape with a heavy pencil line. Using a jigsaw, cut the part staying outside the pencil mark by about 1⁄8″.
Clamp the template in place using the centerlines for accurate positioning, then use a router and pattern bit to trim to the final edge. I used a bit with a bottom-mount bearing to shape my top. (You could, instead, position your template on top of the workpiece then use a top-mounted bearing bit to trim the base unit.)
Though you could make the cut in a single pass, it’s better to make several light cuts until the bearing meets the template edge. Once one section of top is completed, use the centerlines to reposition the template for the next section.
For more contemporary furniture ideas and projects check out “Contemporary Furniture: 17 Projects You Can Build,” now available at ShopWoodworking.com.