I have designed a modular spice rack that can be adjusted to various sizes and can be expanded horizontally in the future. The base design is 4 levels of trays with 3 jars on each level for 12 spices in one rack. I have extended it to hold 36 jars, but if you do not need that large of a rack, components can be deleted to reduce the size. The height of the rack can also be adjusted by deleting individual components in the rails in the 3mf file. The trays do need to be glued to the rail to hold everything together. I just used a bit of superglue and it has been holding up fine. I printed mine in PLA-CF for a bit of extra strength and I liked the look, but it should also be fine in normal PLA which is what I used to validate the small scale design.