Creating custom Slic3r Prusa Edition profiles

Note

These notes apply to the Prusa i3 Mk3 printer. If you are using a different printer, please verify the hardware details are same. These pages may be a bit rough as I revise them and add new material. Please check back regularly for updates.

As of this writing, Slic3r Prusa Edition configuration is broken into 3 distinct sets of configuration profiles:

  1. Printer profiles containing all of the printer hardware settings such as bed size and extruder configuration.
  2. Filament profiles containing all of the filament-specific settings such as print temperatures.
  3. Print Settings profiles containing all of the settings for a specific print job such as layer height and extrusion width.

Creating a printer profile

Set nozzle specifications in printer setting profile

The first step to using a new nozzle size with Slic3r Prusa Edition is to create a new printer profile using the new nozzle settings. Select a printer profile close to the new nozzle. Open the Printer Settings tab, select the Extruder 1 option and adjust the nozzle size and layer height settings under Size.

Slic3r printer setting extruder settings

Fig. 2 Slic3r printer setting extruder settings

  • Set Nozzle diameter to the diameter of the opening on the new nozzle.
  • Set layer height Min to the minimum layer height. 25% of nozzle diameter is a good starting point. The Prusa i3 Mk3 is capable of layer heights as low as 0.05mm and possibly lower.
  • Set layer height Max to the maximum layer height. 120% of nozzle diameter is the recommended maximum layer height. Any higher than this and the hotend places cylindrical extrusions with no “squish” to provide good inter-layer adhesion.

Click the disk icon and save your profile with a new name. I recommend including the new nozzle size in the name.

Customizing G-Code

Slic3r Prusa Edition (and any other slicer for that matter) creates files containing g-code, a series of commands that are sent to the printer for execution. You can customize various g-code sequences that Slic3r Prusa Edition will embed at key points in your print job:

  • Start G-code is sent at the start of the print job, before any actual printing commands are sent. Start g-code will set nozzle and heated bed temps, print the prime line at the start of each print, and a host of other housekeeping functions.
  • End G-code is used to shut the printer down in an orderly fashion. It turns off the heating elements, motors and fans.

Additional g-code sequences can be specified for before and after every layer change. To modify g-code, open the Printer Settings tab, select the Custom G-code option and edit the individual g-code sequences.

For more information on customizing g-code, refer to the custom g-code page.

Modifying G-Code

Fig. 3 Modifying G-Code

Creating a print job profile

Set extrusion widths

To create a print settings profile tailored to the size of your new nozzle, open the Print Settings tab, select the Advanced options and adjust the extrusion widths for different print features.

Slic3r print setting extruder width

Fig. 4 Slic3r print setting extruder width

Note

You can create a single print profile that will work with all nozzle sizes by taking advantage of the auto settings for extrusion widths. Selecting “0” for the width of any feature will direct Slic3r to calculate a width based on the nozzle size when slicing your models. This is a good general-purpose profile.

If you want precision, you will want to create a new profile per nozzle size. For detailed prints, I like to create a profile for each layer height and nozzle size pairing set as follows:

  • External perimeters set to exactly the nozzle size for precision.
  • Internal perimeters either set to exactly the nozzle size, or use Slic3r’s default (1.25 X nozzle size) by specifying 0.
  • 1st layer extrusion widths of 1.2 X nozzle size for adhesion. Wider is a good thing.

As far as maximum extrusion widths, I’ve read that up to the width of the nozzle – including the rim around the opening – will produce good results. Wider than that and you get squishy defects at the edges. You can find good dimensional details on the genuine E3D nozzles, less so on the cheap brass generics. I’m very curious to see what results you guys get going wider than the nozzle opening.

Autospeed settings

I didn’t have much luck with speeds set to 0. I set them to what provides the best balance between function & finish. I’ve got draft and precision print settings profiles. I work on getting a good finish at slow speeds, then gradually increase speeds. At some point, the speeds may put me over the max capacity of the hotend, in which case the max volumetric speed settings throttles it.

Set layer heights

Open the Print Settings tab, select Layers and perimeters options.

Slic3r print setting layer settings

Fig. 5 Slic3r print setting layer settings

  • Set Layer height to the layer height you want to use throughout your print.
  • Set First layer height to a thickness sufficient to provide good first layer adhesion. For nozzle sizes 0.25mm and larger, 0.20mm thickness works well for the first layer. Remember to stay within 80% of your nozzle size.

Set print speeds

Open the Print Settings tab, select Speed options.

Slic3r print setting speed settings

Fig. 6 Slic3r print setting speed settings

Adjust print speeds to suit your quality settings. I recommend basing speeds on the nozzle size you’re using:

  • For fine detail using nozzles smaller than 0.40mm, use the Prusa 0.25mm profile as the basis for speed settings.
  • For larger prints using nozzles 0.40mm or larger, use the Prusa 0.60mm profile as the basis for speed settings.

Open the Print Settings tab, select Advanced options.

Slic3r print setting default speed settings

Fig. 7 Slic3r print setting default speed settings

Adjust print autospeeds to suit your quality settings.

  • Set Max print speed to a reasonable setting for the filament you’re using. 120mm/s or less works well with most filaments.
  • Set Max volumentric speed to your hotend maximum throughput rating. For the E3D V6 hotend used on the Prusa i3 Mk3, 11.5 mm3/s is a good default. See the article on nozzle sizes for more information on maximum volumetric speeds.

Set acceleration rates

Open the Print Settings tab, select speed options and scroll down to the accelration settings.

Slic3r print setting acceleration settings

Fig. 8 Slic3r print setting acceleration settings

Adjust acceleration speeds to suit your quality settings. I recommend basing speeds on the nozzle size you’re using:

  • For fine detail using nozzles smaller than 0.40mm, use the Prusa 0.25mm profile as the basis for acceleration settings.
  • For larger prints using nozzles 0.40mm or larger, use the Prusa 0.60mm profile as the basis for acceleration settings.

Todo

Post-processing scripts

Contact and feedback

You can find me on the Prusa forums or Reddit where I lurk in many of the 3D printing-related subreddits.

Last updated on Oct 29, 2018