After 30 years making sawdust, I'm amazed that I continue to learn something new with each project. It's true even with simple projects like this lazy Susan. At first glance it appears easy, but a closer look reveals an intriguing challenge. The raised rim isn't cut from solid boards, it's created by gluing a series of thin slices of wood together around circular form. The process is called bent lamination, and although I've used it before to add curves to projects, making a complete circle is more of a challenge. But don't let this scare you because you have a distinct advantage over me-you can learn from my mistakes.
I made my lazy Susan 18" in diameter, but size isn't critical. You can adjust dimensions to fit many situations. Just remember, the smaller the diameter, the more difficult it is to bend the wood around the rim successfully.
Build the Bending Form
Successful bent laminations begin with strong, accurate forms. Make the circular bending form for this project from two pieces of medium-density fibreboard (MDF). Start with two pieces of square stock, secured together with 1 1/4"-long screws. Predrill holes to avoid splitting the material, and countersink the heads flush so they're out of the way.
Next, draw diagonal lines from corner to corner to find the centre of the blank, then use this reference point to layout an 18" diameter circle with a compass. If you don't have a large compass, use a stick with a nail driven into one end to serve as the pivot point and a hole drilled in the other to hold your pencil tip.
When preparing bent laminations remember that the thin plies will conform to any flat spots or irregularities on the bending form. That's why you've got to make everything perfectly round. Start by rough cutting the circle with the bandsaw or hand-held jigsaw, keeping about 1/8" away from the waste side of the layout line.
Finish rounding the edges using a straight bit installed in a hand-held router and circle-cutting jig. This assures a perfectly smooth, square edge, in a minimum of time. You can buy a jig, or make your own from 1/4" ply, as I did. In use, the router acts like a power-compass, milling a circle as it rotates. Make several routing passes, lowering the bit about 1/4" with each rotation. Make sure to raise your workpiece on some scrap so you don't mill your benchtop while routing.
Next, drill two 1" diameter clamping holes on each side of the bending form, about 2" in from the edge. These allow you to clamp the laminations to the form. To prevent the strips from sticking to the bending form, rub the edges with a candle, creating a generous coating of wax.
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