MMPR - Modular Model Paint Rack (with STEP files and CAD link)

Overview

The default size is 6 paint bottles per row, which results in rack pieces that will fit most printers. However, the design is fully parametric so you can modify the OnShape document to customize:

• the number of bottle wells per row
• the size of the bottle wells
• the spacing between the bottle wells
• the spacing between the bottle wells and the outside of the rack
• the clearance in the dovetail joints
• the depth of each bottle well
• the height of the risers (e.g. how much higher each new row is)

I only paint D&D minis and only use 25mm paint bottles, so I've only included print files for that size since it's the only one I have experience with. As far as I can tell those are pretty standard, but if there's any demand for other paint systems let me know and I'll upload the models here.

Onshape link: https://cad.onshape.com/documents/4b6974595ded876ef09f4cff/

Assembly

Basic (2 rows)

This small paint rack uses only three parts:

• Front Rack
• Rear Riser
• Rear Rack

Advanced (4 rows)

By printing a few more parts, the basic 2-row design can be expanded as your paint collection grows. In this example, we will upgrade the previous rack from 2 rows to 4 rows. Reuse the three parts from above and print the following additional parts:

• Middle Rack (x2)
• Middle Riser (x3)
• Rear Riser (x2)

The parts can then be assembled like so into a 4-row rack:

Parts list for various configurations

2 rows

3 rows

4 rows

5 rows

𝑛 rows

Adding an additional row

To add a new row (row 𝑛) to an existing rack, print these parts:

• 1 additional rack-middle
• (𝑛 − 2)  additional riser-middle
• 1 additional riser-rear

For example: if you are adding an eighth row to your existing seven-row rack, print one new middle rack, one new middle riser, and 8 − 2 (a.k.a. 6) new middle risers.

An alternative to printing many risers

The risers have a constant cross section, so you could stretch them vertically in the slicer instead of printing multiple copies. The default height is 15mm, so instead of printing three individual risers you could stretch one to be 45mm tall and print that instead.

This is faster and will probably look nicer than printing multiple risers, but it will make the system less modular. For example, you couldn't easily break one big rack down into two smaller ones, since you'd only have one of each specific height of riser instead of many 1-unit-tall risers.

Changelog

v4 (2025-08-14)

Initial release.