When it comes to 3D printing with PLA, it’s essential to understand the importance of post-processing. One of the most common techniques for smoothing out rough surfaces and imperfections is sanding. However, not all sandpapers are created equal, and choosing the right grit is crucial for achieving the desired results.

Grit sandpaper refers to the number of abrasive particles per square inch on the sandpaper’s surface. The higher the number, the finer the grit, and the smoother the surface it produces. When sanding PLA, it’s recommended to start with a coarse grit, such as 80 or 120, to remove any significant bumps or roughness. Then, gradually work your way up to a finer grit, such as 220 or 320, for a smoother finish.

Choosing the Right Grit Sandpaper

When it comes to sanding 3D prints made of PLA, choosing the right grit sandpaper is crucial. The grit of sandpaper refers to the size of the abrasive particles on the sandpaper’s surface and determines how much material will be removed with each pass. Here are a few factors to consider when choosing the right grit sandpaper for your PLA 3D prints.

Factors to Consider

1. Print Quality

The first factor to consider is the quality of your 3D print. If you have a high-quality print with smooth surfaces and minimal layer lines, you may only need a fine grit sandpaper to remove any imperfections. On the other hand, if your print has visible layer lines or rough surfaces, you may need a coarser grit sandpaper to remove more material and achieve a smoother finish.

2. Material Thickness

The thickness of your PLA material is another factor to consider when choosing the right grit sandpaper. If you have a thin layer of PLA, you may want to use a finer grit sandpaper to avoid removing too much material and damaging the print. If you have a thicker layer of PLA, a coarser grit sandpaper may be necessary to remove more material and achieve a smoother finish.

3. Personal Preference

Finally, personal preference plays a role in choosing the right grit sandpaper. Some people prefer a smoother finish and may opt for a finer grit sandpaper, while others prefer a rougher finish and may choose a coarser grit sandpaper.

Recommended Grits

Here are some recommended grits for sanding PLA 3D prints:

• 120 grit: This grit is ideal for removing rough surfaces and visible layer lines from your print.

• 220 grit: This grit is suitable for smoothing out the surfaces of your print and removing any remaining layer lines.

• 400 grit: This grit is perfect for achieving a smooth finish on your print with minimal scratches or imperfections.

It’s important to note that the recommended grits may vary depending on the quality of your print and personal preference. Always start with a lower grit sandpaper and work your way up to a higher grit to avoid removing too much material and damaging your print.

In summary, choosing the right grit sandpaper for your PLA 3D prints depends on several factors, including print quality, material thickness, and personal preference. Recommended grits for sanding PLA prints include 120, 220, and 400 grit, but always start with a lower grit sandpaper and work your way up to avoid damaging your print.

Preparing the Print

Cleaning the Print

Before sanding your 3D printed PLA model, it is important to clean it thoroughly. This will help remove any residual oils or debris that may have accumulated during the printing process. To clean your print, you can use a mild soap and warm water solution. Gently scrub the surface of your print with a soft-bristled brush or sponge, being careful not to damage any delicate features.

Once you have cleaned your print, rinse it thoroughly with clean water and allow it to air dry completely. Avoid using a towel to dry your print, as this can leave behind fibers that may affect the sanding process.

Sanding Techniques

When sanding your 3D printed PLA model, it is important to start with a coarse grit sandpaper and work your way up to a finer grit. This will help you achieve a smooth, polished finish without damaging the surface of your print.

Start by using a 120 grit sandpaper to remove any large imperfections or rough spots on the surface of your print. Use a circular or back-and-forth motion to sand the surface evenly, being careful not to apply too much pressure.

Once you have removed any major imperfections, switch to a 220 grit sandpaper to smooth out the surface of your print. Again, use a circular or back-and-forth motion to sand the surface evenly, applying light pressure.

Finally, use a 400 grit sandpaper to achieve a smooth, polished finish. This will help remove any remaining rough spots or imperfections on the surface of your print. Be sure to sand the surface evenly and apply only light pressure to avoid damaging the surface of your print.

In conclusion, by following these simple steps, you can prepare your 3D printed PLA model for sanding and achieve a smooth, polished finish that will enhance the overall look and feel of your print.

Sanding the Print

Step-by-Step Guide

Sanding is an essential step in post-processing 3D prints made with PLA. It helps to remove any imperfections, layer lines, and rough surfaces, leaving a smooth and polished finish. Here is a step-by-step guide on how to sand your PLA prints:

1. Gather the necessary tools: grit sandpaper (220, 320, 400, 600), sanding block, and safety goggles.
2. Start with the lowest grit sandpaper (220) and use the sanding block to sand the entire surface of the print. This will help to remove any large bumps or ridges.
3. Move on to the next grit sandpaper (320) and repeat the process, making sure to sand in a different direction than the previous grit. This will help to remove any scratches left by the previous grit.
4. Continue sanding with higher grit sandpapers (400, 600) until the surface is smooth and polished.

Tips for Success

Sanding PLA prints can be a time-consuming process, but with these tips, you can achieve a smooth and polished finish in no time:

• Use a sanding block to ensure even sanding and avoid creating dents or uneven surfaces.
• Wear safety goggles to protect your eyes from dust and debris.
• Sand in a well-ventilated area to avoid inhaling dust particles.
• Sand in different directions with each grit to avoid creating scratches in the same direction.
• Use a higher grit sandpaper to remove any scratches left by the previous grit.
• Take breaks as needed to avoid hand fatigue.

In conclusion, sanding PLA prints is an important step in achieving a smooth and polished finish. By following this step-by-step guide and tips for success, you can achieve great results with your 3D prints.

Finishing Touches

Cleaning the Print Again

Before applying any finish, it’s important to ensure that your 3D print is clean and free of any debris or dust. Use a soft-bristled brush or compressed air to remove any loose particles from the surface of the print. If necessary, you can also wash the print with warm water and mild soap to remove any stubborn dirt or residue.

Once the print is clean, let it dry completely before proceeding to the next step.

Applying a Finish

After cleaning the print, you can apply a finish to give it a smooth and polished look. There are several options for finishing a PLA 3D print, including sandpaper, polishing compounds, and spray-on coatings.

One of the most effective ways to finish a PLA print is by using sandpaper. Start with a coarse grit sandpaper, such as 80 or 120 grit, and sand the surface of the print in a circular motion. Be sure to sand evenly and avoid applying too much pressure, as this can damage the surface of the print.

Once you’ve sanded the print with the coarse grit sandpaper, switch to a finer grit, such as 220 or 320 grit, and repeat the process. This will help to smooth out any rough spots and create a uniform surface.

After sanding, you can apply a polishing compound to further enhance the finish of the print. Use a soft cloth to apply the compound in a circular motion, and then buff the surface of the print until it shines.

Alternatively, you can use a spray-on coating, such as a clear acrylic or enamel spray, to protect the surface of the print and give it a glossy finish. Be sure to follow the manufacturer’s instructions when applying the coating, and let it dry completely before handling the print.

Overall, finishing a PLA 3D print requires some time and effort, but the results are well worth it. With the right tools and techniques, you can create a smooth and polished finish that will make your print look professional and impressive.