# Step 4: Attach Part 600_06A

> Fit part 600_06A over actuator ID 4 and fasten it to the existing assembly.

- Page: https://docs.menlo.ai/asimov/1/build/assembly-steps/left-leg-module/thigh-assembly/step-4
- Section: Asimov › Asimov 1 › Assemble Asimov 1 › Assemble › Left Leg Module › Thigh Assembly
- Previous: [Step 3: Install Actuator ID 4](https://docs.menlo.ai/asimov/1/build/assembly-steps/left-leg-module/thigh-assembly/step-3.md)
- Next: [Step 5: Attach Part 600_12A](https://docs.menlo.ai/asimov/1/build/assembly-steps/left-leg-module/thigh-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 |
| - | -: |
| Current assembly from Step 3 | 1 |
| `600_06A` | 1 |
| M4x14 Flat bolt | 6 |
| M3x12 Flat bolt | 6 |
| M3x20 Socket bolt | 1 |
| Threadlocker | As needed |

## Instructions

1. Lay the current assembly flat such that the part `600_05A` is facing downward toward the surface and the actuator shaft is facing towards the ceiling.

2. Take part `600_06A` and align it with the actuator and part `600_03C` such that the actuator fits into the round hollow in part `600_06A` and the 6 holes on the handle align with part `600_03C` threaded insert.

3. Take **6 of** M3x12 Flat bolts and lightly tighten into the 6 holes along the circumference of the round portion of part `600_06A` that is fitting on to the actuator to align the parts.

4. After the parts are aligned:

   > [!NOTE]
   >
   > **Not ready to apply threadlocker?**
   >
   > You can assemble without threadlocker while you check the fit, alignment, and orientation. When you are confident, disassemble as needed, apply threadlocker to the bolts, and reassemble them following these instructions.

   - remove **6 of** M3x12 Flat bolts one at a time in a star formation,
   - apply threadlocker,
   - then tighten them back to secure part `600_06A` to the actuator.

5. Take **6 of** M4x14 Flat bolts and lightly tighten into the 6 holes on the long portion of part `600_06A` that align with the threaded insert on part `600_03C` to align the two parts together.

6. After the parts are aligned:

   > [!NOTE]
   >
   > **Not ready to apply threadlocker?**
   >
   > You can assemble without threadlocker while you check the fit, alignment, and orientation. When you are confident, disassemble as needed, apply threadlocker to the bolts, and reassemble them following these instructions.

   - remove **6 of** M4x14 Flat bolts one at a time,
   - apply threadlocker,
   - then tighten them back to secure part `600_06A` to part `600_03C`.

7. > [!NOTE]
   >
   > **Not ready to apply threadlocker?**
   >
   > You can assemble without threadlocker while you check the fit, alignment, and orientation. When you are confident, disassemble as needed, apply threadlocker to the bolts, and reassemble them following these instructions.

   Take **1 of** M3x20 Socket bolt, apply threadlocker and tighten it into the singular hole at the very edge of the circumference of part `600_06A` to secure it to part `600_03C`.