3D printing produces amazing models, but the raw prints often have visible layer lines and imperfections. To achieve a smooth, professional finish, sanding is essential. However, many people ask: What grit sandpaper should I use for 3D prints?
This guide will break down the best sandpaper grits for 3D printing, detailing how to sand different materials like PLA, ABS, and PETG. You’ll also learn about wet vs. dry sanding, polishing techniques, and tips for achieving a flawless finish.
Table of Contents
Choosing the Right Grit Sandpaper for 3D Prints
Understanding Sandpaper Grit Levels
Sandpaper is categorized by grit numbers, which indicate the coarseness:
| Grit Number | Type | Use Case |
|---|---|---|
| 60-100 | Coarse | Heavy material removal, rough prints |
| 120-220 | Medium | General smoothing, reducing layer lines |
| 320-600 | Fine | Refining surface, preparing for painting |
| 800-2000 | Ultra-Fine | Polishing, achieving a glossy finish |
Best Grits for Different 3D Printing Materials
Different 3D printing materials require specific sanding techniques:
Sanding PLA
- Start: 120-220 grit to remove layer lines
- Smooth: 320-600 grit for refined surface
- Polish: 800-2000 grit if a glossy finish is needed
Sanding ABS
- Start: 100-200 grit to even out rough surfaces
- Smooth: 320-600 grit
- Finish: Use wet sanding at 800+ grit for best results
Sanding PETG
- Start: 220 grit (PETG tends to gum up lower grits)
- Smooth: 400-600 grit
- Finish: Polish with 800+ grit
Wet Sanding vs. Dry Sanding: Which is Better?
| Method | Pros | Cons |
| Dry Sanding | Quick and easy | Generates more dust |
| Wet Sanding | Produces a smoother finish | Takes longer, needs waterproof sandpaper |
For the best results, start with dry sanding and finish with wet sanding.
Common Mistakes to Avoid
- Skipping Grits: Moving too quickly between grit levels leads to uneven surfaces.
- Using Too Much Pressure: Can damage fragile prints.
- Not Cleaning Sandpaper: Clogged sandpaper reduces effectiveness.
- Skipping Wet Sanding: Leads to dull finishes on high-detail prints.
Final Thoughts
Sanding 3D prints is essential for achieving professional-quality results. Choosing the right grit sandpaper and following proper techniques can transform rough prints into smooth, polished pieces. Start with 120-220 grit, refine with 320-600 grit, and finish with 800+ grit for the best outcome.
Would you like to learn more about polishing and finishing techniques for 3D prints? Check out our Ultimate 3D Print Finishing Guide!
FAQ: What Grit Sandpaper Should I Use for Sanding 3D Prints?
What grit sandpaper should I start with for 3D printed parts?
Use coarse grit sandpaper (around 80-120 grit) to initially remove prominent layer lines, blobs, or rough areas quickly.
When to Transition to Medium Grit Sandpaper?
Transition to medium grit sandpaper (150-240) to further smooth out the surface and refine the shape of the 3D printed part.
Why Use Fine Grit Sandpaper?
Fine grit sandpaper (320-400) is suitable for achieving a smoother finish, minimizing visible imperfections, and preparing the surface for post-processing treatments.
What is the Purpose of Very Fine Grit Sandpaper?
Very fine grit sandpaper (600-800) is used for a polished and refined finish, removing remaining imperfections and preparing the part for painting or a glossy finish.
What Precautions Should I Take While Sanding 3D Prints?
Take care to avoid removing too much material, apply even pressure, and regularly inspect the part to prevent over-sanding and distortion.