Improved filament spool holder for Ikea SKADIS

This is an Improved filament spool holder for Ikea SKADIS, a new version of my previous design. 

I decided to make a new version when one of my previous holders collapsed. In this version I used a design with backplates. This has much improved load capacity. Also, now it is possible to have three rows of filaments on a single Skadis board. Unfortunately, to properly mount the backplate, the Skadis board must be unmounted from the wall. That was the only way to achieve adequate load capacity. 

Each holder consists of three parts: Main holder, Middle part and back plate. 

• Main holder comes in two variants; they are the same only mirrored, use appropriate part according to your Skadis board placement. 
• Backplates come in three versions; the larger version is for holders that are NOT in the corners. Smaller back plates go in the corners, there are two versions for left and right corners. 
• Middle part has a dovetail shape and is the same for all holders.
• End parts are holding wooden rods in place. Secure them with M3 wood screws. 

Each holder also needs 9 M4 nuts and M4x25 countersunk screws and a 22 mm (broomstick) wooden rod.

In each corner one M4x25 screw replaces original Skadis button head screw,

Keep in mind that all Skadis boards are held on the wall with two M4 screws. That is probably strong enough, but if you plan to put a lot of weight on single board I strongly recommend to add additional screws in the bottom corners as well.

Supports are only needed for Main holder in the dovetail area. I printed everything in PLA.