Strengthening back panel?

[azk404]

I have built some box shelves that will be hooked to the walls with these - https://www.locksonline.com/Koala-Concealed-Wall-Hanging-Bracket-100mm-x-43mm-6692.html - so as these will be screwing partially into the 12mm ply back panel I would like to strengthen the hold. The main shelf is made from 18mm ply.

As of now its dadoed into the back with a slight lip to conceal the bracket with no nails or screws.

I know want to screw from the top, bottom or sides as these will be seen.

Any other suggestions? Corner brackets? or is it as simple as some small screws around the perimeter of the back?

 

[thick_mike]

I have attached a couple of heavy backless plywood shelving units to walls using a hidden French cleat system.

 

[ozzieguy65]

Hi is there any shelves on the front side of the case or just an outer edge? If shelved screw intro them to lock all together. There is always if all fails is to use plugs to cover the screw heads, in ply not as concealed as solid timber but still looks ok.

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