Best Filament for Sanding – 3D Prints

Sanding is a very important part of the post-processing process. It elevates your 3D models and gives them that smooth, stunning final surface. However, you should be careful when sanding as not all 3D printing filaments can be easily sanded to give a smooth surface.

The easiest filament to sand is PLA, especially PLA composites that are reinforced with materials like metal, wood, etc. You can also sand ABS and PETG to produce high-quality surfaces, but it’s going to take more work than PLA.

In this article, I’ll be giving some tips on how to choose the best filament for sanding and how to sand them properly! So, let’s get started

Best Filament for Sanding – 3D Prints

3D printing filaments have different physical properties that influence how easy they are to sand into a smooth surface. In this section, we’ll be looking at some of the most common 3D printing filaments and how easy they are to sand.

But first, let’s cover safety. Sanding 3D prints produces a lot of fine plastic material that can get into sensitive areas of the body like the eyes, nose, mouth, etc., and irritate them.

To avoid this, make sure you wear protective gear like goggles, facemasks, and gloves while sanding. Additionally, make sure you are sanding in a well-ventilated area to avoid the build-up of these particles.

You can also use a technique called wet sanding to reduce the amount of dust that gets released. This involves adding water or some lubricants to your 3D model while sanding it. This will trap and wash away the plastic particles.

Once you’ve covered all the safety steps, you can start sanding the model.

PLA

One of the best filaments for sanding is PLA, due to its relatively soft and porous physical structure. This makes material removal very easy and you can achieve a high-quality surface with minimal effort

However, you have to be very careful when sanding PLA as it has a low glass transition temperature, so it melts very easily. The heat produced from the friction of the sandpaper can deform your plastic.

That’s why it is advisable not to dwell in one spot for too long while sanding this material. Also, avoid using electric sanders as they can generate a lot of heat.

One user described that they have specifically chosen wood-filled PLA like Hatchbox Wood PLA, because they are easier to sand than normal PLA and many other filaments. After sanding, they produce gorgeous surfaces like the one in the pictures below.

Also, the wood material in the PLA makes it more resistant to heat deformation.

Another great PLA brand for sanding is the Polymaker CosPLA. It is specially made for cosplayers, so it is designed to be easily printed, sanded and painted.

Note: If you’re going to be sanding a PLA model, make sure your print walls are thick enough because the sanding is going to remove a lot of material.

PETG

You can sand PETG to get a smooth, defect-free surface. It is also very heat stable, so you don’t have to worry about it melting or deforming while you sand it. In fact, some users shared that they’ve had some success machining the material.

However, PETG is harder and more durable than PLA, so sanding it is harder than sanding PLA. Also, most PETG brands have a shiny, translucent finish and sanding may ruin this finish.

You can check out this high-quality surface a user got from sanding down a black PETG model.

To get this smooth surface, they followed this process:

• They started sanding with a 180-grit sandpaper to reduce the print texture.
• They then wet-sanded at 600, 1200, and 2000 grit to get that smooth surface.
• To finish off, they polished the part using a microfiber cloth and some polishing compound.
• All this was done with a dual-action polisher/sander which made the sanding easier and faster.

One factor that can hinder the sanding of PETG is that it is slightly flexible, which can make sanding difficult. On a positive note, it is harder than PLA, which means you won’t have to remove as much material to get that smooth surface.

So, you can keep your wall count low.

ABS

You can achieve a smooth, reflective ABS surface by sanding with a bit of elbow grit and patience. You can also use tools like a Dremel and an electric sander with ABS to speed up the sanding process.

It has a high glass transition temperature, which makes it much less likely to deform from the heat sanding produces. However, just like PETG, it is quite hard, which can make sanding difficult.

TPU

Due to its flexible nature, it is very difficult to sand TPU. For this reason, most people, like the user below, prefer using alternative finishing methods like vapor smoothing or going over it with a heat gun.

However, if you still intend to sand it, use light strokes without much pressure to avoid the surface becoming “gummy”. You can also try wet sanding as it extends the life of the sandpaper and keeps it from gumming up with the TPU material removed.

In a nutshell, the filament you choose will determine just how easy your post-processing operations will be. While sanding PLA and PLA composite filaments might be relatively easy, sanding filaments like PETG and TPU might take a little bit more work.

So, tailor your filament selection to your goals, refine your sanding skills and your creations will truly stand out. Good Luck and Happy Printing!