In the 1960s, he worked as a visual effects assistant and stop-motion
animator on The Time Machine (1960), The Wonderful World of the
Brothers Grimm (1962), and The Power (1968). In "The Wonderful World of
the Brothers Grimm", he animated the Puppetoon sequence called "The
Cobbler And The Elves". In "The Power", David animated a squadron of
wooden toy soldiers seen by actor George Hamilton in a store
window.