Hexagonal wooden wallmount shelf (modular, extensible)

It is not the best use of space but it looks great in my office/tinkering corner. The size of the Rack on the Photo is in total 126cm wide. Each board is 250x200x18mm. 

With 250mm boards each Hexagon cell is measures 45cm in height and 50cm corner-corner. You can use longer or shorter boards (see PDF for cutouts).

The whole thing is amazingly sturdy and can bear quite some load, but mounting took almost a morning.

Printing:

• PETG (Das Filament) - for stability
• >66% infill - for stability
• 0.4mm Nozzle
• 0.2 Layers “Quality” Setting in Prusa Slicer

Mounting instructions/hints:

• It is a good idea to create a jig with 6 (or more) thin boards of the same length as your shelf boards to mark and drill the holes. After all you will have to drill 14 holes and a minor deviation may cause a skewed shelf.
• Cut out the shelf boards about 4mm where the joints go otherwise you will have an ugly gap in all corners where smaller stuff falls off the rack.
• Mount the joints with 3.5mm screws and Fischer Dübel (Wall plug? Rawlplug?) 
• Mount the shelf boards with small countersunk wood screws
• Mount the front side joints

The shelf is not entirely my own idea (but my own creation). I have seen something similar on TV before. I really liked it and re-modeled it according to my memory.