# Additional Procedures

## Nozzle Change

The Modix supports nozzle sizes up to 1.4mm in diameter.

NExT Lab readily stocks the following diameters:

| Nozzle Diameter | Use Case                                                                                        |
| --------------- | ----------------------------------------------------------------------------------------------- |
| 0.6             | Best for small to medium detailed prints, large prints will exponentially increase print times. |
| 1.0             | Good for all print sizes, draft to reasonable print resolution. Print times are quick.          |
| 1.4             | Best suited for large prints that have simple geometry. Fastest print times.                    |

#### **Change procedure**

Use supplied torque wrench for swapping nozzles and tightening to the correct tightness.

1. Unload filament completely.
2. Unscrew the nozzle when it is sufficiently cool with the torque wrench.
   1. You may unscrew it when hot, but be wary that it is very hot, use heat-proof gloves.
3. Screw in the nozzle until it is almost tight.
4. Preheat hotend to 240°C.
5. Tighten nozzle with the torque wrench.

<figure><img src="/files/z8vaubSUtGnj6HxobE0B" alt=""><figcaption></figcaption></figure>

## Calibration

### Z-offset calibration (macro)

{% tabs %}
{% tab title="Z-Offset Calibration" %}
Z-offset calibration sets the distance of the nozzle from the bed correctly.

The Modix has a macro for calibrating the z-offset and it is self-guided.
{% endtab %}

{% tab title="BL-Touch Offset Calibration" %}

{% endtab %}

{% tab title="PID Tuning" %}

{% endtab %}
{% endtabs %}

### Griffin BL-touch and nozzle distance calibration (macro)

### PID tuning (macro)

## Bltouch Troubleshooting

The BL-touch pin can be bent and damaged due to collisions during prints.\
As a result, sometimes the BL-touch can't retract and deploy its pin.

The printer will tell you if there are issues with the Bltouch by:

* Red flashing LED on the bltouch unit
* Errors during homing and other procedures
* Visually, it looks bent or broken

You may try the following to troubleshoot:

### Manual Check

Light bumps or collisions may just cause the pin to become stuck temporarily. To fix:

1. Gently pull the pin down.&#x20;
2. Lightly push up with a finger, it should retract partially with a faint snap.
3. Run the test bl-touch macro and it should deploy the probe 10 times repeatedly.
4. Try again if it does not work.
5. If you feel no faint snap when pushing the pin back up, then the probe is definitely broken and you need to inform NExT Lab staff.


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