How To Reduce Layer Shift In 3D Printing
Layer shift in 3D Printing, also known as layer misalignment or layer displacement, is a common issue in FDM (Fused Deposition Modeling) printing. It occurs when the layers of a 3D print do not align correctly, resulting in a skewed or shifted object. Several factors can contribute to layer shifting in FDM printing. Unfortunately with layer shift, majority of the time you only know it’s happened once a print has failed. We've all experienced that feeling of returning to your printer only to find your model has shifted across serval layers and is ruined. Sometimes the printer continues on and prints a bridge or overhang that defies the laws of physics!
What are common causes of layer shift and how to overcome them.
Hardware Issues that can cause Layer Shift
Mechanical Issues
Loose Belts: One of the most common causes of layer shifting in 3D printing is loose belts on the printer's X and Y axis. If the belts that move the print head or build platform are loose or damaged, it can lead to inconsistent movement and layer shifts. Regularly check the belt tension. Some 3d printers have a belt tension test which will give you a threshold the printer needs to be in. An example of belt tension thresholds can be found here. Too lose or too tight may contribute to layer shift. Look for signs of wear near the edges of the belt rubs against the wall of the pulley and replace any damaged belts.
Pulley Problems: Misaligned or damaged pulleys on the printer's stepper motors can cause irregular movements, resulting in layer shifts. Pulleys are normally held in place by one or two grub screws. These can become loose due to the vibrations from the printer. Good practice is to check the grub screw tightness periodically and apply a small dab of low strength Loctite to the thread.
Motor Issues:
Overheating Stepper Motors: Stepper motors can overheat during extended prints or in enclosures with a high ambient temperature. This can affect performance and cause them to miss steps and resulting in layer shifts. When printing PLA or PETG in an enclosure the ambient temperature is recommended to be quite low. PLA 20 to 30 and PETG 25 to 45. Stepper motors can start running into overheating issues with the more advanced engineering filaments like ABS, PC, Peek and Nylon where the compartment temp needed can be as high as 180 (Peek).
Electrical Issues:
Voltage Fluctuations: Electrical fluctuations or power supply issues can disrupt the printer's operation, causing layer shifts. While not a major issue in most parts of Australia, you can stablise the power supply to your print
er through a UPS (Uninterrupted Power Supply) device. These units have come down in price considerably in the last couple of years.
Mechanical Obstructions:
Physical Obstructions: Any physical obstructions or debris on the printer's bed or in the print area can interfere with the print head's movement, leading to layer shifts. We’ve seen a part of a print come lose from the bed, stick to the hotend and knock against the main body of the model causing a layer shift. Falling under the radar of the crash/knock sensor.
Pulley Problems: Misaligned or damaged pulleys on the printer's stepper motors can cause irregular movements, resulting in layer shifts. Pulleys are normally held in place by one or two grub screws. These can become loose due to the vibrations from the printer. Good practice is to check the grub screw tightness periodically and apply a small dab of low strength Loctite to the thread.
Motor Issues:
Overheating Stepper Motors: Stepper motors can overheat during extended prints or in enclosures with a high ambient temperature. This can affect performance and cause them to miss steps and resulting in layer shifts. When printing PLA or PETG in an enclosure the ambient temperature is recommended to be quite low. PLA 20 to 30 and PETG 25 to 45. Stepper motors can start running into overheating issues with the more advanced engineering filaments like ABS, PC, Peek and Nylon where the compartment temp needed can be as high as 180 (Peek).
Electrical Issues:
Voltage Fluctuations: Electrical fluctuations or power supply issues can disrupt the printer's operation, causing layer shifts. While not a major issue in most parts of Australia, you can stablise the power supply to your print
er through a UPS (Uninterrupted Power Supply) device. These units have come down in price considerably in the last couple of years.
Mechanical Obstructions:
Physical Obstructions: Any physical obstructions or debris on the printer's bed or in the print area can interfere with the print head's movement, leading to layer shifts. We’ve seen a part of a print come lose from the bed, stick to the hotend and knock against the main body of the model causing a layer shift. Falling under the radar of the crash/knock sensor.
Software Issues that can cause Layer Shift
Software or G-Code Errors:
Corrupted G-Code: Errors in the G-Code file can cause the printer to execute incorrect movements, resulting in layer shift in 3D printing. This not often found until you see the print playing up. Bad G Code is a rare occurrence so it is not productive to examiner your code through viewer or simulator before each print. Best practise is to re-slice the model and try again.
Software Glitches: Issues with the 3D printing software or slicer can generate faulty G-Code, leading to layer shifting. Again this is a rare occurrence, keep your printer firmware and slicer program up to date to minimise glitches.
Excessive Printing Speed or Acceleration:
Printing at excessively high speeds or with overly aggressive acceleration settings can strain the 3D printer's mechanics and cause layer shifts, especially on larger or more complex prints. If you are increasing your print speed, especially without newly release hardware/software (Input shaping) then you can try:
• Reducing Outer Perimeter Speed - Too higher speed can affect outer perimeters or walls which are crucial for the structural integrity of the print.
• Reducing Travel Speed - Too higher travel speed between print points can overstretch changes in direction leading to misalign of the print.
• Increase Infill Acceleration - Less critical for print quality, this is a great option to pick up some print speed.
• Lower Jerk Control - In most Slicers you have the ability to lower the speed of direction changes. Called Jerk Control, this changes the rate of change of acceleration, smoothing sudden and sharp movements. Lowering these settings in the slicer increases the authority the Jerk Control has over the print.
Software Glitches: Issues with the 3D printing software or slicer can generate faulty G-Code, leading to layer shifting. Again this is a rare occurrence, keep your printer firmware and slicer program up to date to minimise glitches.
Excessive Printing Speed or Acceleration:
Printing at excessively high speeds or with overly aggressive acceleration settings can strain the 3D printer's mechanics and cause layer shifts, especially on larger or more complex prints. If you are increasing your print speed, especially without newly release hardware/software (Input shaping) then you can try:
• Reducing Outer Perimeter Speed - Too higher speed can affect outer perimeters or walls which are crucial for the structural integrity of the print.
• Reducing Travel Speed - Too higher travel speed between print points can overstretch changes in direction leading to misalign of the print.
• Increase Infill Acceleration - Less critical for print quality, this is a great option to pick up some print speed.
• Lower Jerk Control - In most Slicers you have the ability to lower the speed of direction changes. Called Jerk Control, this changes the rate of change of acceleration, smoothing sudden and sharp movements. Lowering these settings in the slicer increases the authority the Jerk Control has over the print.
Other Issues that can cause Layer Shift in 3D Printing
Thermal Issues:
Cooling Problems: Inconsistent cooling of the printed layers can lead to warping or poor adhesion between layers, which can result in layer shifting as the print progresses. Different filament types need a variety of cooling fan control. PLA can have a cooling fan speed set to 100% after the first layer while this setting on an ABS print would cause all types of problems.
Printer Calibration:
Poor printer calibration, including incorrect steps per millimeter (calibration of the printer's motion system), can cause layers to shift as the printer may not move as expected.
To troubleshoot and resolve layer shift in 3D printing, you should start by checking the mechanical components of your printer for any loose or damaged parts. Ensure that belts are tensioned properly, pulleys are aligned, and the printer is on a stable surface. Additionally, review and adjust your printer's settings, such as acceleration, speed, and stepper motor current, as needed. Lastly, carefully inspect your G-Code files and consider re-slicing if you suspect issues with the code.
Cooling Problems: Inconsistent cooling of the printed layers can lead to warping or poor adhesion between layers, which can result in layer shifting as the print progresses. Different filament types need a variety of cooling fan control. PLA can have a cooling fan speed set to 100% after the first layer while this setting on an ABS print would cause all types of problems.
Printer Calibration:
Poor printer calibration, including incorrect steps per millimeter (calibration of the printer's motion system), can cause layers to shift as the printer may not move as expected.
To troubleshoot and resolve layer shift in 3D printing, you should start by checking the mechanical components of your printer for any loose or damaged parts. Ensure that belts are tensioned properly, pulleys are aligned, and the printer is on a stable surface. Additionally, review and adjust your printer's settings, such as acceleration, speed, and stepper motor current, as needed. Lastly, carefully inspect your G-Code files and consider re-slicing if you suspect issues with the code.
Addressing 3D printing layer shift may require a combination of adjustments and may involve some trial and error. Like most errors with 3D printing, regular maintenance is good housekeeping and can help prevent issues like layer shifting from occurring in the first place.
