Why Ghosting Occurs in 3D Printing and How to Avoid It

3D printing, like any manufacturing method, does not come without problems. Besides stringing in 3D printing, where unwanted thin filament threads are stretched between non-printed areas, thus creating ‘strings’ of material, there is also ghosting. You may have heard of this 3D printing phenomenon under a different name, such as ringing, echoing, or even rippling – but they all refer to the same problem. In fact, the term ghosting is very apt, as lines or even entire designs repeat on the part in a weakened manner. This means that if you print a round logo, for example, other unwanted imprints of the logo will be found on your 3D-printed part after the actual printing. Visually, it is analogous to when a stone is thrown into water, making ripples that appear fainter and fainter the further the distance from the impact.

However, these duplicates of previous functions on the printed surface only really become visible when they are hit by light at a certain angle. This often happens during FDM printing as it is common with filaments. Ghosting does not always necessarily affect the entire part, but rather it is a wavy pattern or pattern created by printing vibrations, but which in turn can ruin an entire 3D-printed part. As mentioned before, ghosting effects are caused by the pressure vibration, which can have different triggers. We will now go over these factors and explain what settings you need to make to avoid them in future prints.

The ghosting effect can destroy entire 3D-printed components (Image: Tech2C)

When Does Ghosting Occur and What Can Be Done About It?

When it comes to ghosting in 3D printing, one of the main causes that most people will think of is a print speed that is too fast – and rightly so! While users benefit from a higher print speed because it reduces the overall print time, it also increases the chances of an increased moment of inertia, which can impact drag and thus cause ghosting. If the print head advances at too high a speed, it will require more force to come to a stop so that it can subsequently change direction to continue printing. If you are working with common filaments such as PLA or ABS, then the average print speed is 50 to 60 mm/s, but if this is drastically exceeded, then the risk of ghosting increases. However, in addition to the print speed, you should also pay attention to the travel speed, i.e. when the nozzle is repositioning in between prints, as these can also influence the ghost-like 3D printing phenomena.