Long prints can be both exciting and challenging. The prospect of completing a multi-day project with intricate designs is rewarding, but there’s always the looming risk of print failures. No one wants to spend hours—sometimes even days—working on a print only to find that it’s failed midway through. Fortunately, there are ways to minimize the chances of failure during these long printing sessions.
In this guide, we’ll discuss the best practices and strategies to prevent print failures during long prints. Whether you’re printing large models, multi-part objects, or simply need to ensure that everything goes smoothly, this article will provide the information you need to achieve consistent success in your long printing projects.
Common Causes of Print Failures During Long Prints
Before diving into solutions, it’s important to understand the common causes of print failures that can occur during extended printing sessions. These can include:
1. Inconsistent Filament Flow
Filament flow issues are one of the most common causes of failed prints. These can result from filament jams, clogs in the nozzle, or incorrect extrusion settings. Over time, a print can suffer from inconsistent filament feeding, leading to gaps, layer shifts, or poor adhesion.
2. Print Head or Bed Shifting
For prints that last a long time, the print head or bed may shift due to vibrations, poor calibration, or hardware issues. Even small deviations can cause major print quality issues, leading to failure.
3. Thermal Runaway or Overheating
When a printer is running for an extended period, overheating or thermal runaway (when the printer’s heated bed or hotend reaches temperatures beyond the safe limits) can occur, which can trigger a print failure. These issues often stem from faulty temperature sensors, overheating components, or improper settings.
4. Warping or Adhesion Issues
Long prints are particularly susceptible to warping, especially if the material is prone to it, like ABS. As the print grows taller, cooling and contraction of the filament may cause it to lift off the print bed or cause uneven layers.
5. Power Loss or Electrical Issues
In long prints, the risk of power failure or electrical issues increases. Even minor power interruptions can halt a print midway, wasting hours of work.
6. Inaccurate Z-Axis Movement
During a long print, Z-axis misalignment or inaccuracies can develop. Over time, wear and tear or missed steps can cause the print head to deviate from its expected vertical path, resulting in misaligned layers.
7. Print Environment Factors
Environmental factors, such as temperature fluctuations, drafts, or humidity, can affect how the filament behaves during printing. These factors are more likely to cause issues with long prints that extend over hours or days.
How to Prevent Print Failures During Long Prints: Key Strategies
1. Use High-Quality Filament
One of the easiest ways to ensure the success of long prints is to use high-quality filament. Inferior filaments may have inconsistencies in diameter, leading to extrusion issues. They can also absorb moisture, which can cause clogs and print defects. To avoid these issues, always opt for reputable filament brands and store the filament properly in airtight containers with desiccants to prevent moisture absorption.
Tips:
- Choose filaments known for their stability and reliability during long prints, such as PLA, PETG, or ABS.
- Keep your filament dry in a moisture-controlled environment to prevent poor prints.
2. Perform Proper Bed Leveling
Bed leveling is critical to ensuring proper adhesion during long prints. A misleveled bed can result in poor adhesion and warping, leading to failed prints. During long prints, slight misalignments can cause significant issues, especially with larger models.
Tips:
- Always perform manual or automatic bed leveling before starting any print.
- Use a paper method or a leveling probe to ensure even distances between the nozzle and the bed across all corners and center.
- Consider using an auto-bed leveling sensor to maintain consistent leveling during long prints.
3. Ensure Proper Print Adhesion
Ensuring proper adhesion is crucial for long prints. If the first few layers don’t adhere to the bed properly, your print will likely fail during the process. Using an adhesive, such as painter’s tape, glue stick, or specialized print adhesion sheets, can help improve the chances of a successful long print.
Tips:
- Use a heated print bed to improve adhesion, particularly when printing with materials like ABS or PETG.
- If you’re printing with materials prone to warping (like ABS), consider using a heated bed along with a brim or raft to increase adhesion.
- Consider using a specialized surface like PEI (Polyetherimide) or a BuildTak sheet for better adhesion and easier print removal.
4. Check the Printer’s Calibration
Proper calibration is essential for long print success. Calibration includes ensuring your extruder is correctly calibrated, checking the bed level, and confirming that the Z-axis is aligned. Incorrect calibration can cause under-extrusion, poor layer bonding, and uneven surfaces.
Tips:
- Calibrate your printer before starting any long print job. This ensures that every component is aligned and working correctly.
- Perform a test print with smaller objects to ensure calibration is correct before committing to long prints.
5. Monitor the Print Regularly
While monitoring a long print in real-time may not always be possible, regular checks during the process can help catch issues early. You can install cameras or use print monitoring software to watch your print from a distance and receive alerts if something goes wrong.
Tips:
- Use a camera setup like OctoPrint or a 3D printer with built-in Wi-Fi capabilities to monitor your print remotely.
- Check the print during key intervals, such as after the first few layers are printed, to ensure that the print is progressing smoothly.
6. Prevent Thermal Runaway and Overheating
Long prints may push the printer’s temperature limits. Thermal runaway protection is a critical safety feature that ensures the print head and bed don’t overheat. If you’re using a printer without thermal runaway protection, it’s highly recommended to add this safety feature. Additionally, ensure that the cooling fans are functioning well and that no components are obstructed.
Tips:
- Ensure your 3D printer’s firmware includes thermal runaway protection, which will stop the print if there are any temperature irregularities.
- Keep the fans and cooling systems clean and functioning properly to prevent overheating during long prints.
7. Reduce Print Speed and Layer Height for Better Stability
For long prints, reducing the print speed can improve the overall print quality and reduce the likelihood of errors. Slower speeds allow for more precise extrusion and better layer bonding. Similarly, printing with a larger layer height can reduce the number of layers needed and therefore decrease the chances of a failure.
Tips:
- Slow down the print speed to 30–40mm/s for long prints to ensure better quality and reduce the risk of print failure.
- Use thicker layers (e.g., 0.2mm or higher) for prints that need to last for extended periods, as it reduces the chances of issues caused by layer adhesion or extrusion.
8. Invest in a High-Quality Power Supply and UPS System
Power loss is one of the most common reasons for print failures in long prints. A sudden power outage can cause the print to stop abruptly, ruining the progress made. To prevent this, you can invest in an Uninterruptible Power Supply (UPS) or a power backup system to keep your printer running in case of power interruptions.
Tips:
- Use a UPS to ensure that your printer can continue running in the event of a power failure.
- Invest in a reliable power supply that can handle the printer’s needs over long sessions.
9. Maintain and Clean the Printer Regularly
Routine maintenance and cleaning are essential to keeping your printer in good working condition for long prints. Dust, filament debris, or old lubrication can cause mechanical issues, affecting the print quality and performance during extended sessions.
Tips:
- Clean the printer regularly, especially the print bed, extruder, and cooling fans, to ensure smooth operation.
- Lubricate the moving parts of your printer, particularly the Z-axis and lead screw, to reduce friction and improve precision.
10. Check for Proper Environmental Conditions
Environmental factors such as temperature, humidity, and airflow can affect the print quality, especially for long prints. Drafts, sudden temperature changes, or humidity can cause warping, layer separation, or poor adhesion.
Tips:
- Place your 3D printer in a stable, controlled environment to prevent drafts and temperature fluctuations.
- Consider using an enclosure or print chamber to maintain consistent temperature and humidity levels, especially for filaments like ABS or Nylon.
Conclusion
Long prints can be a test of patience and precision, but by following the best practices outlined in this guide, you can significantly reduce the chances of print failures. From proper bed leveling and filament quality to careful monitoring and environmental control, these strategies will help ensure that your long prints are successful. With the right setup, tools, and precautions, you can confidently tackle even the most complex, multi-day 3D printing projects and achieve professional-quality results.