.. _retraction_calibration:

.. meta::
   :description lang=en: Fighting 3D printing stringing - Part 2: Calibrating retraction settings

Fighting Stringing Part 2: Calibrating retraction settings
----------------------------------------------------------

*Stringing is one of biggest frustrations in 3D printing. In these notes, I'll summarize simple steps to reduce stringing by calibrating slicer retraction settings.*

Fighting fine stringing is one of the most frustrating problems to pin down, and our slicers provide numerous work-arounds to help us deal with this problem:

* retraction and de-retraction length
* retract/de-retract filament speeds
* wiping
* z-lift or z-hop
* coasting (Cura)

Unfortunately, the testing process can be a long and tedious process. It is particularly frustrating to test individual small prints with different printer settings such as retraction.

.. important:: Be sure you've :ref:`calibrated your slicer filament settings <filament_calibration>` before trying to find the perfect retraction settings. Retraction and related settings are work-arounds for imperfect extrusion results. Calibrate your filament settings first to match your slicer extrusion settings to your real-world printer and filament settings first to reduce the number of work-arounds required to get good results.

One trick is to use a "virtual multi-extruder" printer profile to create a multi-part single print with unique hardware settings for each part.

.. include:: 3dprinting_disclaimer.rst

The idea is to create a printer profile with multiple extruders and enter different settings for each extruder. Assign each part to a different extruder and you can (with a bit of patience) generate several tests with a single print as shown below.

.. figure:: ../_images/3dprinting_techniques_retraction_calibration_slicer.*
    :alt: Retraction calibration print
    :width: 100%
    :align: center

    Retraction calibration print

It's a little cumbersome, but it beats trying to track multiple tiny prints. Here's an example showing several retraction setting modifications:

* Retraction length is set to 0.2mm
* Lift Z is set to 0mm
* Retraction speed is set to 50mm/s
* Deretraction speed is set to 25mm/s

.. figure:: ../_images/3dprinting_techniques_retraction_calibration_settings.*
    :alt: Extruder settings
    :width: 100%
    :align: center

    Extruder settings

Provided each part is small enough, you can produce a single print that compares multiple settings.

.. figure:: ../_images/3dprinting_techniques_retraction_calibration_results.*
    :alt: Retraction calibration print results
    :width: 100%
    :align: center

    Retraction calibration print results

.. note:: Thanks again @Ringarn67 for catching the filament override error in the sample file! I've removed the example settings for now to avoid confusion.

I use the following retraction settings as a starting point:

* 0.2-0.4mm retraction
* 0-0.2mm z-lift
* 50mm/s retract speed
* 25mm/s de-retract speeds

.. seealso::

     * :ref:`Fighting Stringing Part 1: Calibrating filement settings <filament_calibration>`
     * :ref:`Calibrating maximum volumetric rate <calibrating_volumetric_rate>`

.. include:: 3dprinting_footer.rst

Last edited on Aug 13, 2021. Last build on |today|.