[SOLVED] Locking Shelves

Hey there, first post. Been watching this project for over a year now, but only jusy been able to finally go for it.

So, Ive just build my first multiboard “wall” an 8×4 grid of 8×8 tiles on a custome made workbench. This particular project is planned for tools.

My first additio I wish to make is some multibins in various sizes for the storage of wood screws, I plan to print off “bins” in either 1×1, 1×2 or 2×2 depending on screw length. These will then sit on a shelf, which will be attaced to the multiboard grids via rails.

How do I “lock” the shelves to the rails to stop them sliding left and right?

(I have a horrible feeling the answer if “Once you print it you will see” as has happened with a few other things.

O, by the way, my opinion of multiboard. Looking at you tube videos and the files you can see the brilliance of it all, but its not until you start to print it all off you start to see the Genius of it all. Well done