One of our
trap doors was designed by our local school's shop class.
It's is one solid door, as all the bi-fold systems either failed or were to dangerous.
The locking
system is like that of a dunk-tank.
There is a builders-right triangle underneath the
trap, supporting the actuall door.
Then there is a arm that holds the triangle in place. It is rigged on a quick-release hinge. The
trap stays in place nicely, and when we are not using it there is a small arm that pivots underneath to support the other side of the
trap.
When we did Sweeny Todd a few years ago, we used a tunnel slide underneath, so we could
drop the company head-first through the
trap and they would slide down the childrens tunnel-slide until they were horizontal, where they just climbed out of the slide. Unfortunately, the
bend in the slide was such that they came out of the slide very fast, and we had to make a foam pit at the end for them to land into. It was very fun as the
drop was from the second story of the home, or about 15 feet.
Here is a link to an
image to help explain the
trap better