So what should you use a cleaver for? They come in a variety of weights and specs, PinchOfSalt says on Chowhound. A cleaver with a thin blade (say, 2 millimeters) and a steeply angled edge does a good job with vegetables. A heavy cleaver with a thick blade (8 millimeters or more) and a wide edge with a shallow angle is better for hacking up bones.
A heavy cleaver is better for "wedging," breaking up food rather than making clean slices, JavaBean says. (Chemicalkinetics thinks a thin blade is best for such cleaver tasks as cutting hard winter squash like butternut.) And while a Chinese cleaver is the same general shape as a Western one, it's an entirely different animal. Most Western cleavers are built for meat-chopping. Chinese cleavers range in thickness, but it's only very heavy ones that are appropriate for cutting through bones, khuzdul says.
By the way, a medium-weight knife is probably better than a cleaver for performing noncutting tasks like smashing garlic cloves, and a medium-weight knife will cut through chicken bones, but a heavy cleaver (and maybe even a saw) is necessary for thick bones. Chemicalkinetics likes the Chan Chi Kee brand Kau Kong Chopper (model KF 1402), a short, thick, carbon-steel knife available in specialty knife shops in Chinese neighborhoods. The heavy tip gives it extra momentum during the swing, and it easily breaks down and debones a chicken.
Discuss: Heavy, but not too heavy, cleaver?