Hi all !
We were tired of using masking tape to prevent water and sand to come out of the sides of the door during cuts, so I made those 3D printed joints : https://www.thingiverse.com/thing:6030521
They just snap on the sides of the acrylic door et work perfectly !
Spacing between the side of the door and the frame is not the same on both sides, but I guess it can vary on each machine, so I uploaded the Fusion360 file as well so you can make your own adjustments.