Here are some photos of how our platform bed is put together. The wood is 3/4 inch birch plywood, the hinges are brass piano hinges, and aluminum angle is used to create the “box” portion and other supports.
View from the back:
My method for holding the platform in place:
The platform is hinged in such a way as to form a seat (from before we had a drawer):
View with platform removed (looking towards the back of the van):
We have a drawer under the bed that is also used to support the front edge of the platform:
Small pieces of wood “flip up” to prevent the drawer from sliding back:
Pins, set in brass bushings, are used to hold the seat closed, as well as hold the platform in the “upright” position:
Countersunk bolts are used to connect the “box” to the floor:
I removed the metal plate that was used to support the bench seat and replaced it with a piece of plywood with brass inserts - I have heard of others keeping the metal plate in place, and sliding the box into the angle pieces on this plate - that is a pretty slick idea!