Main printing parameters

Extrusion Temperature

It is essential to consider the extrusion device and the nozzle in order to get the best results when working with PLA filaments. The temperature range of this filament is quite large, ranging from 180°C to 230°C. For darker colours, a temperature increase of 3°C to 5°C is usually recommended.

In order to get the most accurate parameterisation for your 3D printer, you can perform a temperature test.

Printing Surface

It is not crucial to use a heated bed when working with PLA, but it is strongly advised, especially for large prints, to improve adherence and prevent warping. The optimal temperature for these kinds of prints is between 50°C and 65°C. If a heated bed is not available, a lacquer or surface prepared for 3D printing such as magnetic strips with textured sheets or PEI sheets must be used. Kapton tape or masking tape may also be used for this purpose.

Printing speed

Having a general idea of the optimum print speeds for a 3D printer is very important, as it is contingent on the whole set of components. Having said that, 35mm/s to 65mm/s would be an optimal range for most instances.

Advance printing parameters

Retraction

An optimal value must be determined through a retraction test when using this parameter, which depends on the hotend-extruder assembly.

The following retraction values are provided as a starting point:

• Direct Extrusion (Prusa MK3S, Artillery X1 or similar): 1mm and 35mm/s
• Short Bowden (Ender 3 or similar): 4mm and 40mm/s
• Long Bowden (CR10, Tevo tornado or similar): 5mm and 40mm/s

Other printing parameters

Flow

The purpose of this parameter is to absorb the dimensional variations of the filaments, therefore a flow test must be conducted to determine the precise value for each material in the printer where it will be used. This parameter should not shift more than 5% in a normal print, meaning it must be between 95% and 15% in order to maintain consistency. If our extruder is badly calibrated after performing the flow test, we must calibrate it first in order to achieve the best results.

Extrusion width

Using slicers, you can usually set the percentage at which the material is laminated to 120% of the nozzle diameter, which is a decent value. The nozzle diameter, however, cannot be set below the nozzle diameter. You may increase the thickness of the walls in a single pass to produce stronger parts without increasing the printing time by adjusting this value.

Layer Fan

When parts have a lot of detail, it is important to help the plastic solidify correctly; otherwise, it will solidify too quickly. It is not recommended to turn on this fan in the first layers in order to enhance the part's adhesion to the surface.

Unload filament

Leaving the filament loaded in the printer and leaving the hotend at printing temperature is the primary cause of jams with this material. This deteriorates the material and eliminates its plastic properties, resulting in residues inside the hotend that are deposited on the next printing job, which results in poor quality results or even nozzle blockage.

Retractions

The hotend will get clogged if the material cools down and adheres to the walls of the barrel if the retraction length is not well defined and excessively long. A shrinkage test should be performed as escribed above to prevent this.

Type of hotend

When printing with PLA, the hotend with a PTFE tube along its entire barrel is the finest choice in order to avoid friction between the material and the metal walls of the hotend itself. If you have an all-metal hotend, you may also print with PLA, but you must keep the melting temperature low and make sure the heatsink has a decent thermal shock in order to prevent the molten plastic from rising along with the barrel.

Hotend cooling

It's imperative to have a cooling system when creating a thermal shock in order to prevent the molten material from rising up the barrel. Typically, a fan is used which is turned on at the same time as the 3D printer and should not be switched off. There are also some hotends that utilise liquid cooling for this purpose.

Cleaning

It is important to clean the hotend if a material with a higher melting point than PLA has been used, so that the new material can flow without problems.