How to Make a Coopered Basket Without Math
Peter Lutz demonstrates jigs he uses so that he can work safely and accurately, building a coopered basket with sides that cant outward
Synopsis: Light and graceful but quite strong, coopered containers combine elegance with approachable construction. Whether you make a design with vertical sides or sides that angle outward, one of the challenges is figuring out how best to cut, joint, and rout the small parts. Here, Peter Lutz demonstrates jigs he uses so that he can work safely and accurately, building a coopered basket with sides that cant outward. Lutz’s system of wedges allows you to cut the compound angles without math.
After making coopered pieces with vertical sides, I began building some with sides that splay. I’ve used this basket as a centerpiece on the dining table and to bring a dish to a potluck—it definitely makes my contribution look better. Building the basket is similar in most respects to making the coopered trays. The key differences (apart from creating the handle) relate to making the sides splay outward.
Splayed and coopered
When you make a coopered vessel with vertical sides, the staves are rectangular—their sides are parallel. But in a coopered piece with sides that lean outward, the staves are trapezoidal—wider at the top than at the bottom. Typically, such parts are made by angling the tablesaw blade to make the bevel, while also angling the miter gauge to create the trapezoidal taper. Because the staves are tapered, the bevel angle isn’t the same as for a vertical-sided piece. Divining the correct angles for the taper and bevel settings can be complicated. I found a website that will make calculations for you, and I’ve done coopering that way, but then I discovered a far simpler and virtually math-free method. By making a wedge to the angle of splay I want (9° in the case of this basket) and using it to support the workpiece during machining,…