> For the complete documentation index, see [llms.txt](https://khalil-lab.gitbook.io/evolver/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://khalil-lab.gitbook.io/evolver/extensions/custom-fluidics/adding-a-third-pump-rack.md).

# Adding a Third Pump Rack

## Parts

1. Buy another pump rack from Fynch
2. 2X - [3D printed pump extension mount (Front)](https://github.com/FYNCH-BIO/hardware/blob/master/Fluidics%20Box/Pump%20Mounts/Pump_Expansion_V2/3dmount_frontExpansionRack.STL)
3. 2X - [3D printed pump extension mount (Back)](https://github.com/FYNCH-BIO/hardware/blob/master/Fluidics%20Box/Pump%20Mounts/Pump_Expansion_V2/3dmount_backExpansionRack.STL)
4. 2X - [40-20 aluminum tubing](https://www.amazon.com/Aluminum-Extrusion-European-Standard-Anodized/dp/B08X4P2XLN?th=1)
   1. Final length 5.7 inches (144.78mm)
5. 8X - [M6 x 1 mm Thread, 12 mm Long Screws](https://www.mcmaster.com/92010A424/)
6. [M6 x 1mm tap](https://www.mcmaster.com/8305A17/)
7. 2X - [2x8 ribbon cable](https://www.digikey.com/en/products/detail/assmann-wsw-components/H3CCH-1618G/1218799)

## Protocol

### Machine 40-20 Aluminum Tubing

Do for both of the aluminum rails. Diagram can be found [here](https://github.com/FYNCH-BIO/hardware/blob/master/Fluidics%20Box/Pump%20Mounts/Pump_Expansion_V2/40x20_aluminum_rail.PDF).

1. Cut to final length 5.7 inches (144.78mm)
2. If necessary, drill out the hole on each side so that your M6 x 1mm tap can work
3. Tap each side with M6 x 1mm tap

### Assembly

1. Unscrew 4 screws from top of original pump mount
2. Remove 20-20 aluminum tube
3. Replace with 40-20 tube. Screw in
4. Add 3D printed extenders
5. Screw in 3D printed extenders
6. Slot pump rack in
7. Plug in ribbon cables