# Step 4: Prepare the Actuator Housing

> Install seven M4 square nuts in part 300_14C and retain them with three M4x16 Socket bolts and four M4x25 Socket bolts.

- Page: https://docs.menlo.ai/asimov/1/build/assembly-steps/right-arm-module/upper-arm-assembly/step-4
- Section: Asimov › Asimov 1 › Assemble Asimov 1 › Assemble › Right Arm Module › Upper Arm Assembly
- Previous: [Step 3: Prepare the Bearing Housing](https://docs.menlo.ai/asimov/1/build/assembly-steps/right-arm-module/upper-arm-assembly/step-3.md)
- Next: [Step 5: Connect the Shoulder Cable Connectors and Position the Actuators](https://docs.menlo.ai/asimov/1/build/assembly-steps/right-arm-module/upper-arm-assembly/step-5.md)

> [!IMPORTANT]
> **Assign actuator IDs before assembly**
>
> Assign and verify all 25 actuator IDs before assembling the robot. The robot will not work correctly with missing or incorrect IDs. IDs must be assigned one actuator at a time on the bench; you may need to disassemble the robot if you skip this step. See [Assign Actuator IDs](https://docs.menlo.ai/asimov/1/build/assembly-preparations/assign-actuator-ids.md).

## Parts needed

| Part | Count |
| - | -: |
| `300_14C` | 1 |
| M4 square nuts | 7 |
| M4x16 Socket bolt | 3 |
| M4x25 Socket bolt | 4 |

## Instructions

1. Take part `300_14C`, put it on a flat surface with the inner hollow part facing upward

2. Put **3 of** M4 square nuts into the 3 slots on the surface of Part `300_14C`

3. Using **3 of** M4x16 Socket bolts and lightly tighten it on the circumference of Part `300_14C` where you have previously inserted the square nuts to secure the square nuts in place first. If you overtighten, the actuator will not fit in later on.

4. Put **4 of** M4 square nuts into the 4 slots on the round circumference of Part `300_14C`

5. Using **4 of** M4x25 Socket bolts and lightly tighten it on the circumference of Part `300_14C` where you have previously inserted the 4 square nuts to secure the square nuts in place first.