Tips for better prints - HackMD

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Introduction

With some care and preparation your Voron printer is able to produce high quality prints in a wide range of materials. This page contains some of the tips and best practices collected from the Voron community.

For practical purposes this page focuses on printing with ABS filaments on a Voron 2 series printer. However; many of these tips will translate to other printer models and filaments.

If you are looking for some inspirations and impressions stop by the #voron-showcase channel in the Voron Discord.

Filament Choice

3d printing filaments from different manufacturer will vary in formulation and physical properties which causes them to behave vastly different. Even filaments from the same manufacturer may show different characteristics depending on the filament color and sometimes even the batch of the filament.
Not all manufacturers will meet the dimensional tolerances they specify for their filaments, you may want to invest in some measuring tools and verify their claims.

When picking a filament include price and availability into your considerations:

  • A “boutique material” may have a prohibitively high cost or limited availability… the one spool you got may print great, but it doesn’t do you any good once it’s empty.
  • “Cheap as dirt” filament is often cheap for a reason, be mindful of particulates in the filament, dimensional tolerances and quality of the moisture seal.

If possible, try different filaments from different brands and find some that work for you and your printer. Once you found a filament stock spare spools depending on your printing habits.

Depending on your local climate you may want to take extra precautions when storing opened filament spools for longer periods of time. Unless you live in a dry climate consider purchasing a large airtight container and some desiccant packs for medium/long term storage.

If your printer is in a humid environment (your basement may qualify as humid) consider building a “filament dry box” to protect your filament at all times.

Printer maintenance

  • Periodically check the printers hardware and make sure all components are properly attached and securely fastened. Check printed parts for stress signs (white discoloration) and cracks.

  • Pay attention to the X carriage. You should not be able to rock the printhead up and down. If you can move it check the seating of the Quick Change Toolhead and the attachment of the carriage to the linear movement.

  • Verify the proper seating of the PTFE tube, it must be inserted all the way and must not rock in and out. If the tube backs out check the filament path and coupler.

  • Check the hotend, make sure it does not wiggle and is securly fasted. If you are using a V6 make sure the block is properly attached to the heatbreak.

  • Dust near a pully is indicative of a belt rubbing on the flange of a pully. This will introduce unwanted artifacts into the print and should be resolved.

  • Periodically check belt tension. Belts will stretch during their break in period. If the belt consistently looses tension check for a hardware fault.

  • Check the extruder for filament shavings and other debris. If you find an exessive amount the filament path may be obstructed.

  • Relubrication of the movement is only required every few thousend hours if the recommended lubrication was used. Oil based lubrication may need to be reapplied on a much short schedule.

  • Other consumeable need to be replaced on a suitable schedule. PTFE tubes on a 500-1000h schedule, nozzles and PEI as required. Refer to the Consumables section.

Preparation/Startup routine

A consistent print preparation and startup routine is essential in achieving consistent print results.

  1. Clean print chamber
    Dust and debris will collect in your print chamber and may transfer to the print if left unchecked. Periodically remove any dust and debris by wiping down all surfaces or by the use of compressed air.

  2. Clean print surface
    The print surface needs to be dust, oil and fat free as those will impact print adhesion. Clean the print surface with a suitable degreaser before every print. Isopropyl alcohol (IPA) is readily available and an excellent degreaser.

  3. Flex-plates / removeable surfaces
    If you are using a flexplate, springsteel or other type of removeable print surfaces be mindful of it’s orientation and the printers state. Depending on orientation of the plate and temperature of the bed the surface may deform slightly different causing inconsistent print results.
    Always install the flex-plate in the same orientation and the same bed state (hot vs cold). Tests with springsteel sheets seem to suggest that they are best installed after the bed has reached temperature and had time to equalize.
    If you are placing it on a hot bed use appropriate PPE to prevent burn injuries.

  4. Bed temperature
    The bed temperature reading mat does not reflect the temperature of the print surface, rather it reads the temperature of the heater mat. In addition, the plates temperature might require an additional 10+ minutes to equalize.

  5. Chamber temperature
    The print chamber of a Voron 2 is passively heated by the print bed. As the temperature in the chamber has a direct impact on material expansion and some of the sensors found inside the printer let the temperature reach a stable point before starting a print. This process can take upwards of 30 minutes.
    Set the bed temperature to the desired temperature for printing and let the printer “heat soak” until the chamber temperature reaches a stable point in the >40°C range.

  6. Axis movement
    Repeatedly moving the printer’s axis over the full range of movement can help with the consistency during leveling/homing and initial layers. This can be combined into the “heat soak” and used to prevent timeouts.

  7. Homing and gantry leveling
    The inductive probe used for Quad Gantry Leving (QGL) is sensitive to temperature changes. Ensure that the chamber temperature is stable before running the QGL. The QGL can run with the hotend at temperature or with a cold hotend, experiment to see what gives you the most consistent results for your printer.
    The final homing before the start of a print must be done with a fully heated hotend to ensure repeatability of the z position.

  8. Hotend heating, ooze and purge
    During heatup filament may ooze from the nozzle, remove this from the nozzle prior to the final homing operation. The ooze may cause inconsistency in the homing and transfer to the print.
    Filament left in the heated zone of the hotend for prolonged period of times will deteriorate. Use slicer generated purge features (e.g. “skirts”) or dedicated purge line to fully remove the “toased” filament from the heated zone prior to printing any actual parts.

Slicer choice

All modern mainstream slicers are able to produce high quality prints when properly configured for your printer. The Voron community maintenances a set of slicer profiles that you can use as a known good starting point for further tuning.

Proper understanding of slicer settings will have a tremendous impact on print results. Try to learn more about your favorite slicer and tweak the settings to meet your needs.

While using different slicers for different kinds of prints can be beneficial avoid blindly hopping between slicers and slicer profiles just because someone posted a nice print sliced with a different slicer.

Consumables

3d printing filament is not the only consumable of the printer. Nozzles, PTFE tubes and the PEI print surface are also considered consumables and need periodic replacement.

Consider the shipping time for your consumables and if required stock at least one full set of replacement parts.

The PTFE tube will wear due to friction of the filament and should be replaced on a 500h schedule to ensure the best possible print results.

Nozzles will wear depending on the nozzle material and filament used or may simply clog due to dust and debris entering the filament path.
Brass nozzles will wear even with unfilled filaments, consider replacing them on a schedule to ensure consistent print results.

The PEI surface may get scratched or otherwise damaged by the removal of prints. While keeping a spare sheet is considered good practice consider the ~1 year shelf life of the 3M 468mp sheets that are used to glue the PEI to the plate.
In addition PEI is not immune to acetone and it will develop cracks with frequent usage of acetone.