On Thingiverse / Github there are the details for making a 6″ rack system, It is designed for being built from 2020 extruded aluminium profile1. the measurements are as roughly as follows:
| Dimension | Measurement | |
| inches | mm | |
| Front panel width | 6.1 | 155 |
| Holes centre to centre | 5.2 | 135 |
| Maximum usable aperture | 4.4 | 115 |
| 1 U Height | 0.55 | 14 |
| 2 U | 1.1 | 28 |
| 3 U | 1.65 | 42 |
| 4 U | 2.2 | 56 |
The standard 19″ rack mounting system has the following measurements:
| Dimension | Measurement | |
| inches | mm | |
| Front panel width | 19 | 482.6 |
| Holes centre to centre | 18.31 ± 0.06 | 465 ± 1.5 |
| Maximum usable aperture | 17.7 | 450 |
| 1 U | 1.75 | 44.8 |
| 2 U | 3.5 | 88.9 |
| 3 U | 5.25 | 133.4 |
| 4 U | 7 | 177.8 |
I like the look of the 6″ system, however to fit my needs better; I am going to adjust it slightly:
| Dimension | Measurement (mm) | Fusion 360 link |
| Front panel width | 170 | |
| Holes centre to centre | 150 | |
| Maximum Unit depth | 170 | |
| Maximum usable aperture | 130 | |
| 1 U | 15 | 1U case |
| 2 U | 30 | 2U case |
| 3 U | 45 | 3U case |
| 4 U | 60 | 4U case |
This means that each Front Panel is just slightly shorter than 4 19″ rack units at 177.8mm, leaving ~3mm each at top and bottom for sheets of material. and the Maximum usable aperture is 450 mm which is 30 U in my system, so with careful mounting and design; I should be able to get 30 U of equipment in 4U of 19″ Rack mount space.
The parts on Thingiverse are designed to be printed; however I am more interested in making my system to be laser cut, using the same box maker for Fusion 360 as I am using on my MiniBoyGeekInterface.
For mounting into the 2020 I will use the same method, and use M3 x 6 Thumb Screws.
