Popular Woodworking 2000-02 № 113, страница 10

Cris Cuts

Circles Without a Band Saw

Three great jigs for your table saw that can cut circles and even bowls.

You can cut perfect circles — even bowls—on your table saw using these three jigs and what I call the "pivot-guidance technique." This technique is the same for all three jigs. With each, the work piece rests on a pivot point, and you turn the work over the blade, making light passes until you reach the desired shape.

Perfect Circles

This jig is great for transforming a square piece of wood into a round one. You start by removing the bulk of the waste stock by making tangent cuts, a chore with a miter gauge and not something to do freehand. But the operation proceeds quickly and safely with a simple jig—just a platform kerfed for the saw blade and guided by a strip that rides in the table slot.

Prepare a piece of plywood for the platform and use a strip of hardwood for the guide (see the drawing titled "Platform for Tangent Cuts"). Set the rip fence 6" from the blade and run a kerf in the platform about 15" long. Leave the platform in place while you slip the guide strip into position. Hold the guide in place by tack-nailing through the platform. Then in-

Photo by Al Parrish

To create a circular component, first make tangent cuts to remove the bulk of the waste stock. Both the work and the jig are moved past the saw blade in repeat passes with the work rotated after each pass. Although not shown in the photographs, use the guard.

After the waste is removed, clamp the jig so the centerline of the work is in line with the front edge of the saw blade.Then hold the work firmly and rotate it slowly against the blade's direction of rotation. Set the blade height so it's adequate for the thickness of the stock.

The jig can be used to produce multi-sided figures. Mark the work for the number of sides needed so it can be aligned with a line on the platform that is at a right angle to the blade.An octagon, for example, requires two perpendicular diameters.

10 Popular Woodworking February 2000