Les Claypool's one-string Whamola is the mutated and high voltage bastard-son of the washtub bass. Using a lever tuning/playing system, the instrument delivers globular, freak-out sounds. Just watch this video to get an idea...
We've seen many plans posted n the net for building your own, but none come as close as Jeremy Cook's plans (links below). Just in time for Autumn instrument building season, we're sharing them with you.
Plans links are in 2 parts - the body and the electronics: