How to surface finish 3D printed parts

Author: Aaron Chen  Date Posted:21 July 2019 

A 3D printed part is still a incomplete product after it comes out from a 3D printer. Thus, it will at least require some amount of post-processing particularly in aesthetic terms and functionality. This is where surface finishing comes in. It is a technique that turns a raw 3D printed part into a finished product.

The geometry of the 3D part and the material used will determine what type of finishing method can be used for a specific 3D part. Moreover, achieving different textures and appearances will depend on the technique being used.

Below are some of the different surface finishing techniques for 3D printed parts with some tips on how to handle it properly.


After removing the 3D part from the printer, there may be thin lines where each new layer begins. For some industrial components, this imperfection may not matter. But for prototypes, customer goods and display items, the 3D parts are preferred to be as aesthetically pleasing as possible.

Sanding is a popular and easiest finishing technique in 3D printing. This method involves using a type of rough material like sandpaper to smooth out the surface. It also removes any imperfections on the 3D part.

To have better results, the proper way is to sand in small circular movements across the surface of the 3D part. It is advised to avoid sanding in only one direction particularly in the direction of the stepping lines. It is because it can result in striations or trenches in the 3D part.

There are also some materials that are very easy to sand such as ABS. Thus, it is crucial to be very careful not to overdo it. It will be enough to only remove as little as 0.010 inches to clear out any stepping layers.

Bead blasting

Another most used finishing process for 3D printing is bead blasting. In this method, little beads are blasted against a 3D part to smooth out its appearance.

It is a finishing technique for smoothing out areas that are difficult to reach like undercuts and holes. This is done by using a spray gun and plastic media to remove layer lines from the 3D part. This process may only take about five to ten minutes to complete depending on the size of the 3D part.

The advantage of this technique is its flexibility. It can be performed whether a product is still in the prototyping stage or production stage. When done, it will give the 3D part a smooth matte surface appearance.


This method is mostly used to polish metals. It is also used to soften materials such as ceramic, plastic or synthetic.

In this method, the 3D part is placed into a vibrating unit containing a soft media. This unit is rotated by a machine for hours until the media polishes the part’s surface.

One of the advantages of tumbling technique is that many 3D parts can be placed into a unit and processed at once whereas working on it one at a time.

Vapour smoothing

Vapour smoothing works by melting the surface of the 3D part using a solvent. This process involves the exposing of the 3D part to a vapour chamber for seconds resulting in liquefied plastic.

After that, the part is immediately placed in a cooling chamber to halt or stop liquefaction. This process will result in a smooth and shiny 3D part.

This method is also used to fill pores on the 3D part’s exterior. It makes it useful to seal a 3D part that is intended to hold liquids or gases.


Plating is a process of covering a part with metal to give the parts additional functionalities and benefits. For plastic plating, some of the most common metals that can be used includes copper or nickel and even gold or silver. unfortunately, this technique will make the plastic 3D part prone to damage from impact, wear and other external issues.

This process can also be used for metal components. It offers beautiful colouration and enhances the appearance of the metal 3D part. Moreover, this method is used to increase resistance to corrosion, oxidation, improves strength and enhances other functional benefits.


Surface finishing is important since some 3D parts may need some enhancements on its surface finish. This means that it should be a design consideration and needs to be planned and decided beforehand. It will not only enhances the appearance of the 3D part but also improves its functionality.

If you need help with your 3D printing project, there is a 3D printing service company that has you covered. They have 3d printing engineers and 3d designers in-house to provide services such as 3D design and modelling, custom 3D printing, industrial 3D printing and many more.

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