How Do You Make A Three Pendulum Rotary Harmonograph?
• Start by building a sturdy table. This table top is a 3’x3′ square of 3/4″ thick plywood. The legs are 1½” x 1½” square and about 37″ long, with triangular braces cut from 1½” x 8″x 12″ wooden pieces. The legs are splayed out slightly to give the table strength, and to allow the rotary pendulum to swing without hitting a leg. • Screw and/or glue the braces to the legs first, and then cut their tops together at a slight angle with a table or circular saw. • Adjust the leg lengths to give a table-top height of about 37″. • If you want to be able to fit the table through doorways without taking off the legs, you might need slightly shorter legs and pendulums. • Drill holes for the pendulums. Drill 3 holes of 3″ diameter through the table surface for the pendulums to hang through. The hole for the rotary pendulum should be centered in a corner about 8″ from each side just clear of the leg brace underneath. The other two holes should be aligned near the opposite edges, about 8″ from the c
