---
title: "Queue"
description: "A queue holds print jobs until a printer starts them. The printer's own queue and the group queue in Dashboard."
url: https://developer.formlabs.com/core-concepts/queue/
---

# Queue

A *queue* holds print jobs until a printer starts them. Each printer has its own
queue, which holds the print jobs uploaded to it. Each Printer Group also has a *group
queue*, the Fleet Control queue in Dashboard, which holds the print jobs sent to the group
until a printer in the group is ready.

## How a print job moves through the queues

A print job goes to one printer's queue, or to a group queue that hands it to the
first ready printer:

```mermaid
flowchart LR
    code["print_scene"] -- "printer: serial name" --> pq["Printer queue"]
    code -- "printer: queue ID" --> gq["Group queue<br/>(Dashboard)"]
    gq -- "a printer is ready" --> pq2["Printer in the group"]
    pq --> start["Operator starts<br/>the print job"]
    pq2 --> start
```

## Queue a print job on a printer

The `print_scene` method with `print_now=False` does what **Upload to Queue** does in
PreForm: it uploads the print job to the printer's own queue. An operator starts it on the
printer's touchscreen when the build platform is ready. For more information, see
[Starting a print job on the printer touchscreen](https://formlabs.com/support/Starting-a-print-job-on-the-printer-touchscreen/).

![The Queue tab on a Form 4L touchscreen with three uploaded print jobs. Each shows its material, resin volume, and print time, and the first one is expanded with a start button and a delete button.](https://developer.formlabs.com/assets/images/support/f4l-queue.png)

*The printer's own queue on a Form 4L touchscreen.*

## Send a print job to a group queue

To send a print job to a Printer Group, pass the group's queue ID as the `printer`. The
queue ID is the `dashboard_queue_id` field in the group's device record, and PreForm must
be logged in to the account that owns the group:

```python
# A queue ID as the printer sends the print job to the group queue.
job = preform.print_scene(
    scene_id=scene.scene_id,
    printer=QUEUE_ID,
    job_name="bracket",
)
```

A group queue can't start a print job immediately, so `print_now=True` fails with
`OPERATION_FAILED`. When PreForm can't find the queue within
`find_printer_timeout_seconds`, 30 seconds by default, the operation fails with the same
error. For more information, see [Group](https://developer.formlabs.com/core-concepts/group.md).

## How a group queue picks a printer

Dashboard sends the next print job to a printer in the group when that printer is
ready to print with the right consumables. Until one is, the print job waits in the
queue. In Dashboard, an operator reorders, duplicates, and deletes queued print jobs:

![A group queue in Dashboard with four queued print jobs. Each is unassigned and waits for a printer with a matching configuration.](https://developer.formlabs.com/assets/images/support/fleet-control-reorder-queue-jan-2023.png)

*Reordering a group queue in Dashboard.*

A printer takes print jobs from the group queue only with remote printing turned on:

![The Remote printing and monitoring setting on a Form 4 touchscreen, turned on.](https://developer.formlabs.com/assets/images/support/f4-remote-printing-and-monitoring.png)

*The remote printing setting on a Form 4.*

For more information, see
[Using Group Queues in Dashboard](https://formlabs.com/support/Using-Group-Queues-in-Dashboard/).

## What's next

- [Tracking print progress with Dashboard](https://formlabs.com/support/Tracking-Print-Progress-with-Dashboard/)