I made this spool holder to fit in the corner next to my wife's sewing machine to keep the them close but also out of the way. 

Each segment will hold 10 spools and can be mounted next to another segment with two pins to keep the spacing so you only need to install 4 screws, two in the top and two in the bottom. 

The spool holder jig will help you in the location of the screws and also ensure that the segments are installable.

Print 12 (number of segment) - 2 pins. 

Print in the orientation they are created.

I used generic black PLA.

Let me know if you print this, I like to see pictures of my designs in the wild.