Linear Rail for DSLR Camera

This is a linear rail for a dslr camera made from 1/8" think laser cut acrylic and some 12mm linear rails/bearings. The hole on the center sliding piece for the camera mount fits a 1/4-20 bolt (standard for camera mounts). If you are planning on mounting this to a tripod the bottom piece should have another layer to it or use some other kind of reinforcement to reduce the slight amount of sag in the middle from the weight from the linear rails. I would have chosen smaller rods/bearings but I alr