Creating a model for 3D printing can seem intimidating at first. The following article will give you a basic guideline to make sure that your design is 3D printable. Please note that materials and finishes can have their own specifications, which you can inform yourself on the the information on the material pages and design guidelines of our website.

1. Wall thickness

In 3D printing, wall thickness refers to the distance between one surface of your model and its opposite sheer surface. It is important that every surface of your 3D model has been designed with a wall thickness and that the value corresponds to the minimum specifications of the printing material and finish. For an overview of wall thicknesses per material see the article: What is the minimum wall thickness for a material?

In the image on the left you can see that the surfaces have not been designed with a thickness. In the picture to the right, you can see that all surfaces have a wall thickness.

2. Make sure that all surfaces are closed

A model needs to be completely closed in order to make the file suitable as input for a 3D printer. Make sure that all surfaces are well attached to each other and that there are no holes. Imagine that the inside of your model were to be filled with water, the model would need to be watertight and no leaks should occur. If you do have holes in your model, please close them by stitching the surfaces together in your 3D software program. 

This design is not watertight, notice the missing triangle in its surface at the bottom right corner.

3. Intersections and internal overlaps

From time to time intersections and walls can appear as artefacts / remains as a result of certain operations in the design process. These structures within a design can confuse 3D printers about what exactly you want to print and can make the model unprintable. Please remove all excess structures before uploading the file for ordering.

In the picture above, the shape marked red is most likely an artefact from the hole construction, which can be caused using a Boolean operation (a function that helps to merge or substract several overlapping elements from each other). The red structure needs to be removed before printing.

4. Surface orientation, inverted normals and reversed faces 

Another problem that can occur is the phenomenon of inverted normals or reversed faces. Most 3D modeling programs distinguish between the inside and outside of a surface in order to determine the model’s volume. A reversed face or inverted normal means that the surface of your model is facing in the wrong direction. It is important that you double-check your file and make sure that all normals are facing the correct direction.

5. Small details and embossed or engraved text 

Details or small decorative parts of an object such as embossed or engraved text, need to be of a certain size or they will not appear on the 3D printed model. The exact minimum size of the smallest possible features of the design depends on the selected material. That’s why you need to carefully read through the design guidelines of the material. Sticking to the minimum detail size will make sure that everything is as readable as you intended.

6. Hollowing and escape holes

A hollow model means that the interior of your object will not be solid. Solid designs are not necessarily a problem, depending on the material they will be stronger and harder to break, but they will also be more expensive as more 3D printing material is used.

With a hollow model, the interior of your print will in theory be empty. However, since our printers print layer by layer, 3D printing material can get trapped in the interior of your model (see the image in the middle below). If you would like to avoid this, you will need to add ‘escape holes’ to your design. Material that was not solidified during building your 3D print can then be removed during post-processing.