I routinely wear a derby hat around town. So when the Halloween season approaches, I feel the need to wear a hat that really makes a statement. I decided to combine my fondness for old-style hats with my love of mechanical automata. The result is this trick top hat. A little monster hides insides the hat and springs out of the top whenever I squeeze a hidden hand lever.
To create a hat that's tall enough to house the mechanism, combine 2 costume top hats -- sold as "coachman's hats" -- into one large hat. Cut the top off one hat. This will serve as the base hat, which will sit on your head and hold the mechanism base.
Cut the top and brim off the second hat. Later, this tubular piece will form the upper half of the hat. Save all the pieces.
The mechanism is a 4-bar linkage-a wooden parallelogram with 2 horizontal and 2 vertical bars.
There are 2 fixed pivot points at the rear of the 4-bar linkage, and 2 swinging ones in the front. The 4-bar linkage amplifies a short pull from the cable into a larger upward motion of the front-most vertical bar.
Fit the rubber finger puppet over the top of the front-most bar of the linkage. Attach a spring to the base and the front bar, to pull the monster back into the hat when the hand lever is released.
I am an artist who creates contemporary wood automata with humorous and magical themes. I write on the subject for blogs, magazines, and books. I also consult on various mechanical and automaton-related things.