How to Get Rid of 3D Print Lines

3D printing has revolutionized the world of design and manufacturing, allowing creators to turn digital models into physical objects with remarkable precision. However, a common issue that many 3D printers encounter is the appearance of visible print lines on the surface of the printed object. These lines, often caused by layer inconsistencies or imperfections in the printing process, can detract from the overall quality of the print. If you want to improve the finish of your 3D prints, it's important to understand how to get rid of these 3D print lines effectively. In this article, we’ll walk you through several methods for eliminating or reducing the visibility of print lines and achieving a smoother, more professional-looking result.

Best Ways to Get Rid of 3D Print Lines

1. Sand the Printed Object

One of the most common and effective ways to remove 3D print lines is by sanding the printed object. Sanding allows you to smooth out the surface by removing excess material, especially where the print lines are most visible.

Step 1: Begin by using coarse-grit sandpaper (around 100-200 grit) to remove the most prominent print lines.

Step 2: Work in small, circular motions to even out the surface. Focus on areas where the lines are most noticeable, applying more pressure to those sections.

Step 3: Once the major lines are smoothed out, switch to finer-grit sandpaper (around 400-800 grit) to refine the surface and reduce any roughness.

Step 4: Finish with an even finer grit (1000-1500 grit) for a polished, smooth finish.

Step 5: After sanding, clean the print thoroughly to remove any dust or debris.

Sanding is a straightforward and highly effective way to smooth out print lines, but it can take time and effort depending on the size of the print and the depth of the lines.

2. Use a Chemical Vapor Smooth (For ABS Prints)

For prints made with ABS filament, a chemical vapor bath can be an excellent solution to remove print lines. This technique uses the vapor of a solvent like acetone to smooth the print, effectively dissolving the outer layers of the print.

Step 1: Place your ABS print inside a vapor chamber (a sealed container where you can safely expose the object to acetone vapors).

Step 2: Heat acetone in a container, ensuring that it creates vapor but doesn’t boil or spill. Use a container that has proper ventilation.

Step 3: Expose the object to the vapor for several minutes (usually 5-15 minutes, depending on the size and detail of the print). The vapor will smooth the surface by slightly melting the outer layer of the print.

Step 4: After the process is complete, remove the object and allow it to cool and harden before handling.

This method works best for ABS prints but should be approached with caution due to the flammability of acetone and the potential for over-smoothing if left too long.

3. Use Filler Primer for Smoothing

Filler primer is a specialized spray paint designed to fill in small imperfections, including print lines, while also providing a smooth surface for further finishing work.

Step 1: Choose a filler primer suitable for the material of your print. Ensure the print is clean and free of dust or grease before applying the primer.

Step 2: Shake the filler primer can well and apply a thin, even coat to the entire surface of the print.

Step 3: Allow the primer to dry completely (usually 15-30 minutes, depending on the brand).

Step 4: Once dry, use fine-grit sandpaper (around 400-800 grit) to smooth the primer and remove any rough spots.

Step 5: Repeat the process, adding additional layers of primer and sanding in between, until the surface appears smooth and free of print lines.

Filler primer is ideal for smoothing large areas or prints with noticeable layer lines. It’s also a great option if you're preparing the print for painting or additional finishing.

4. Polish the Object Using a Buffing Wheel

After sanding and smoothing the print, you can use a buffing wheel to further polish the surface and eliminate any remaining print lines. This method is especially effective for creating a glossy, smooth finish on your 3D prints.

Step 1: Attach a soft polishing pad or buffing wheel to a rotary tool or Dremel.

Step 2: Apply a small amount of polishing compound to the wheel or directly to the print’s surface.

Step 3: Turn on the rotary tool and gently buff the surface of the print, moving in small, circular motions.

Step 4: Be cautious and don’t apply too much pressure, as this can cause the print to become overly polished or even damaged.

Step 5: After buffing, wipe the surface with a soft cloth to remove any compound residue, leaving behind a smooth and glossy finish.

Buffing works well for smaller prints or when you want a high-gloss finish. It’s especially useful after sanding and priming for a professional-quality result.

5. Improve Print Settings (For Future Prints)

Preventing 3D print lines from appearing in the first place is often the most effective strategy. By improving your printer settings, you can minimize the visibility of print lines and create smoother prints overall.

Step 1: Adjust your layer height. Printing with a smaller layer height (e.g., 0.1mm instead of 0.2mm) can reduce the appearance of print lines because it creates finer layers.

Step 2: Increase the print temperature. Printing at a higher temperature can help the filament flow more smoothly, which may reduce layer lines.

Step 3: Reduce print speed. Slower print speeds allow the extruder to lay down the filament more precisely, resulting in fewer visible lines.

Step 4: Use a different filament. Some filaments, like PLA, tend to produce smoother prints than others. Experimenting with different filaments might help reduce visible lines.

Step 5: Calibrate your 3D printer. Ensuring that your printer is properly calibrated will help with better layer adhesion and alignment, reducing the chances of print lines.

Adjusting your print settings can help improve the quality of future prints, making it a worthwhile investment in terms of both time and material cost.

Other Ways to Get Rid of 3D Print Lines

1. Use a Smoothing Machine: Some professional 3D print smoothing machines are designed specifically for smoothing prints made of materials like ABS. These machines use heat and/or chemicals to create a smooth finish.

2. Heat Gun Technique: Using a heat gun on the surface of the print can help melt the outer layers and reduce the visibility of print lines. However, this method requires precision to avoid damaging the print.

3. Try Resin Coating: For resin prints, a resin coating or epoxy can be applied to fill in gaps and smooth the surface. After applying, you may need to sand the object for the best results.

4. Post-Processing Software: Certain software tools, like Meshmixer or Blender, allow for mesh smoothing and optimization, which can reduce the appearance of print lines before printing begins.

5. Apply a Clear Coat: For prints that need a glossy finish, applying a clear coat of lacquer or acrylic can help mask print lines and provide a smooth appearance.

Things to Consider

1. Material Type: When attempting to remove or reduce print lines, the material of your print plays a significant role in the ease and success of post-processing. Materials like PLA are generally easier to work with in terms of sanding and smoothing, while ABS or PETG prints may require more advanced techniques like vapor smoothing or filler primer. Be sure to choose the appropriate method for the specific filament you're working with.

2. Time and Effort: Some methods, such as sanding and polishing, can be time-consuming, especially for larger prints. If you’re looking for a quick fix, using a chemical vapor smooth or filler primer might be more efficient. However, for high-quality, professional-level results, methods like sanding and buffing may require more effort but provide a much smoother finish.

3. Printer Calibration: Improper calibration of your 3D printer can result in visible print lines that are harder to remove through post-processing. Regularly calibrating your printer, ensuring correct nozzle height, and checking the extrusion rates can help reduce the occurrence of visible layer lines in your prints. If you find that print lines are consistently visible, check the calibration of your printer before focusing on post-processing methods.

4. Printer Settings for Future Prints: While post-processing methods are helpful for existing prints, the best way to avoid visible print lines in the future is by improving your printer settings. Reducing layer height, optimizing print speed, and experimenting with different filament types can help achieve a smoother finish straight off the printer. Make sure to spend some time fine-tuning your printer before committing to a print job.

5. Material Safety: When using chemicals like acetone for vapor smoothing or when applying primer or paint to your prints, always be mindful of safety precautions. Ensure that you are working in a well-ventilated area, using gloves and safety goggles when necessary, and following all manufacturer instructions for the products you're using.

Conclusion

Getting rid of 3D print lines is an achievable task with the right approach and tools. Whether you choose to sand your print, use chemical vapor smoothing, or apply filler primer, there are several methods that can help you achieve a smoother, more professional finish. Additionally, by optimizing your printer settings and materials for future prints, you can reduce the occurrence of print lines and achieve high-quality results straight off the printer. Post-processing can be a time-consuming but rewarding process, allowing you to bring your 3D printed creations to life with a polished, clean appearance.