Found these really useful large Storage Organisers at Homebase only these ones have a proper pair or hinges not a thin plastic leaf which breaks off after a couple of dozen uses.

The only snag with them was that at only 17 very large compartments, they were begging for some additional dividers.

So, here is my solution. There are three different sized dividers, the small divider fits and splits the four mid-section outer compartments into two whilst the larger divider splits the mid-section centre four.

The Front Dividers splits the two very large front compartments into two on the left and two on the right.

The final comment to my offerings is that unlike the very many storage cases like this, these hold all the contents securely and separately when stowed on a shelf vertically.

You can review the item on the following link.
http://www.homebase.co.uk/en/homebaseuk/clear-502-organiser-with-18-divisions-114301

Prints quite easily in PLA without a raft or support