You can suspend the chandelier from an adjustable brace, a steel bar that hangs between the joists from two sharp-pronged metal feet. Most braces are rated to support a fan weighing up to 70 pounds if the joists are spaced 16 inches on center. But if they're 16 to 24 inches apart, the brace can only handle up to 35 pounds.
It fits in the hole made for the box in the ceiling, and the brace is extended with a threaded portion of the brace to bite into the joists on either side.
[This message has been edited by Ron (edited 11-05-2005).]