> For the complete documentation index, see [llms.txt](https://mujoseph.gitbook.io/mujoseph-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mujoseph.gitbook.io/mujoseph-docs/emma-mk1-drsstc/hardware-overview/mechanical-design/ebox-assembly.md).

# Ebox Assembly

## Overview

The Ebox Assembly is the main body of the *Emma Mk1* and encloses all electronic sub-assemblies, excluding the [primary coil](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/electrical-design/primary-coil.md) and [secondary tank circuit](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/electrical-design/secondary-tank-circuit.md).

<div data-with-frame="true"><figure><img src="https://2297250131-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzNHSl7dsTOS0XjlMXnIe%2Fuploads%2F7l2IYsjRbogUV0yjZrgL%2Fimage.png?alt=media&amp;token=724eaec9-dfdd-4eb2-bba2-72bb4b9778ba" alt=""><figcaption><p>Emma Mk1 Ebox Assembly</p></figcaption></figure></div>

### A: Ebox left panel

**Material:** 0.177" (4.5 mm) clear acrylic sheet

**Fabrication:** [SendCutSend](https://sendcutsend.com/) sheet cutting service

### B: Instrument panel

<div><figure><img src="https://2297250131-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzNHSl7dsTOS0XjlMXnIe%2Fuploads%2FKne2BOPxiU2nAhPTfBgu%2Fimage.png?alt=media&amp;token=0860ed69-1e15-48d9-aac5-38ebf5b37828" alt=""><figcaption><p>Ebox instrument panel ( front )</p></figcaption></figure> <figure><img src="https://2297250131-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzNHSl7dsTOS0XjlMXnIe%2Fuploads%2FOTogvD9sylCSt6gMb2Ni%2Fimage.png?alt=media&amp;token=2dc91023-d7de-425a-8c5f-35c264e7e5ab" alt=""><figcaption><p>Ebox instrument panel ( back )</p></figcaption></figure></div>

The instrument panel contains an off-the-shelf AC power monitor, reporting mains voltage and current. The PWR (power) and ACT (activity) panel mount LEDs are routed to the [Raspberry Pi](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/raspberry-pi.md) GPIOs, and the red momentary push-button is used to wake the Raspberry Pi from sleep. The STA (status) LED and white push-button are routed to the [Motherboard PCB](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/electrical-design/pcb-design/motherboard.md).

**Material:** PETG

**Fabrication:** 3D printed

### C: Air vent cover (4x)

**Material:** PETG

**Fabrication:** 3D printed

### D: Ebox top hatch cover

**Material:** PETG

**Fabrication:** 3D printed

### E: Ebox back panel

**Material:** 0.125" (3.2 mm) MDF sheet

**Fabrication:** [SendCutSend](https://sendcutsend.com/) sheet cutting service

### F: Ebox bottom platform

**Material:** 0.5" (12.7 mm) MDF sheet

**Fabrication:** [SendCutSend](https://sendcutsend.com/) sheet cutting service

### G: Caster wheel (4x)

**Fabrication:** Off-the-shelf

### H: Back hatch

**Material:** PETG

**Fabrication:** 3D printed

### I: Ebox top panel

**Material:** 0.220" (5.6 mm) clear polycarbonate&#x20;

**Fabrication:** [SendCutSend](https://sendcutsend.com/) sheet cutting service

### J: Ebox front panel

**Material:** 0.118" (3 mm) clear acrylic sheet

**Fabrication:** [SendCutSend](https://sendcutsend.com/) sheet cutting service

### K: Ebox front panel column

**Material:** PETG

**Fabrication:** 3D printed

### L: Ebox column (4x)

Referring to the image below, each Ebox column consists of three separate sections. The sections are attached using a [mortise and tenon](https://en.wikipedia.org/wiki/Mortise_and_tenon) (`C`) approach. The mortise and tenon junction is then secured with an M3 screw (`E`).&#x20;

The adjoining Ebox acrylic panel (not shown) is secured within the column panel slot (`D`). M4 threaded inserts (`A`) along with accompanying screws fasten the column to the [Ebox top panel](#i-ebox-top-panel) and [Ebox bottom platform](#f-ebox-bottom-platform).

The two front columns also have cavities (`B`) for press-fitting 8x3 mm neodymium magnets, used for holding the[ Ebox front panel](#j-ebox-front-panel) in place via the mated [Ebox front panel column](#k-ebox-front-panel-column).

<div data-with-frame="true"><figure><img src="https://2297250131-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzNHSl7dsTOS0XjlMXnIe%2Fuploads%2FIiaCrvDVchWSqmsET5Xd%2Fimage.png?alt=media&amp;token=eeb8b7af-e068-4ef8-bf38-e59b1f7cb5b7" alt="" width="563"><figcaption><p><em>Emma Mk1</em> Ebox Column (for the front right of the Ebox assembly)</p></figcaption></figure></div>

**Material:** PETG

**Fabrication:** 3D printed

### M: Ebox right panel

**Material:** 0.177" (4.5 mm) clear acrylic sheet

**Fabrication:** [SendCutSend](https://sendcutsend.com/) sheet cutting service

## Active Cooling

The *Emma Mk1* uses three 120 VAC, 110 CFM, axial muffin fans to actively cool the high-voltage electronics.

<div data-with-frame="true"><figure><img src="https://2297250131-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzNHSl7dsTOS0XjlMXnIe%2Fuploads%2FSkc0LjBIlPeXBcBs12HI%2FScreenshot%202026-09-15%20213629.png?alt=media&amp;token=38b94d51-2073-494c-a5a7-823a9756ce1b" alt="" width="284"><figcaption><p>Axial 5" Muffin fan (source: Amazon.com)</p></figcaption></figure></div>

The three muffin fans are mounted to the [PCB Rack Assembly](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/mechanical-design/pcb-rack-assembly.md) via 3D-printed PETG brackets and fastened with M3/M4 screws (see below).

<div data-with-frame="true"><figure><img src="https://2297250131-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzNHSl7dsTOS0XjlMXnIe%2Fuploads%2FgzfVXJ91JfgGfMUJUjND%2Fimage.png?alt=media&amp;token=406e9d90-2686-4d6e-8fbd-1d6e1d19b729" alt="" width="563"><figcaption><p><em>Emma Mk1</em> Active Cooling</p></figcaption></figure></div>

Active cooling: muffin fans pull cool air from the intake port (image above, bottom left), force the air across the [*MMC Bank*](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/electrical-design/pcb-design/mmc-bank.md), [*Half-Bridge*](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/electrical-design/pcb-design/half-bridge.md), and [*Voltage Doubler*](/mujoseph-docs/emma-mk1-drsstc/hardware-overview/electrical-design/pcb-design/voltage-doubler.md) PCBs, and vent the waste heat through the three exhaust ports (image above, right side).

<div data-with-frame="true"><figure><img src="https://2297250131-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FzNHSl7dsTOS0XjlMXnIe%2Fuploads%2F0lLjwX5Iv9H3Uac3KLzl%2FFront%20Panel%20Enhanced.png?alt=media&amp;token=0c30d6a5-976e-4d79-90e2-d3516fa750b3" alt="" width="563"><figcaption><p><em>Emma Mk1</em> Ebox Assembly internals ( physical )</p></figcaption></figure></div>