# Step 6: Attach the Torso to the Pelvis

> Secure the torso waist plate to waist yaw actuator ID 23 on the completed pelvis module with six M4x20 Socket bolts.

- Page: https://docs.menlo.ai/asimov/1/build/assembly-steps/torso-module/attach-lower-half-and-wiring/step-6
- Section: Asimov › Asimov 1 › Assemble Asimov 1 › Assemble › Torso Module › Attach Lower Half + Wiring
- Previous: [Step 5: Attach the Arm Modules](https://docs.menlo.ai/asimov/1/build/assembly-steps/torso-module/attach-left-and-right-arms/step-5.md)
- Next: [Step 7: Install the RPU and Connect Its Cable Connectors](https://docs.menlo.ai/asimov/1/build/assembly-steps/torso-module/attach-lower-half-and-wiring/step-7.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 |
| - | -: |
| Torso-with-arms assembly from Step 5 | 1 |
| Completed pelvis and lower-body assembly | 1 |
| M4x20 Socket bolt | 6 |
| Threadlocker | As needed |

## Instructions

1. Set up part `100_01C` such that the neck is facing the ceiling and the waist is facing the ground.

2. Take the Pelvis Module and place it in a stable position such that the pelvis surface is facing the ceiling. Then take the Torso Module and align its waist portion with the Pelvis module. Make sure that the 6 holes on waist plate `100_02A` are aligned with the 6 holes on EC-A6416-P2-25 actuator (part `200_10X`) (ID 23) of the Pelvis module. Also, make sure that the crescent-shaped cable channel is aligned and that the pelvis cables pass through without being pinched.

3. Take **6 of** M4x20 Socket bolts and lightly tighten into the 6 holes on part `100_02A` to align the Torso Module and Pelvis Module together.

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** M4x20 Socket bolts one at a time in a star formation,
   - apply threadlocker,
   - then tighten them back to secure Part `100_02A` and the actuator together.