If you like this but don't want to get your hands as dirty, have a look at the Crazy Clock: https://www.tindie.com/products/nsayer/crazy-clock/ I got one for my daughter. The erratic ticking eventually became a distraction when she was studying, so we have retired it for now. But we got a lot of amusement out of it.
Yeah, the main problem with this project is you have to find a silent 3.88 analog clock to attach it to.
Last cheap clock i've tried was silent on half the circle and kinda buzzy on the other half. It had seconds so that meant the ambient noise changed every 30 seconds...
Oh wait. Maybe I should open it up and remove the seconds needle. Time for a totally analog project!