Six Ways to Guarantee Your 3D Model will be Printable
17 February 2017
Any quality 3D printed product — whether it’s a prototype or production part — begins with a quality file, with all data properly checked and any errors repaired. A process for preparing the 3D model for printing should be established as part of an effective workflow management plan, with the appropriate systems and tools put in place to minimise any chances of human error.
As your foundation, before sending any file to 3D model for conversion into STL format for printing, consider the following six areas:
1) Will your 3D printer and choice of material be suitable for this project? Check the capabilities of your 3D printer in advance to ensure that your model will be sent to it in a compatible file format and that the build platform will accommodate its dimensions. This will help develop a more efficient volume packing process. Also, consider your choice of material; will it be suitable for producing any fine details in your model during printing? Will you require your part to be dyed or painted following printing?
2) Wall thickness. Will the finished part be sufficiently durable, bearing in mind the choice of material? You may find that for larger, more complex designs, it is best to opt for slightly thicker walls in order to avoid cracks appearing after printing.
3) Will there need to be any holes factored into the design to let out excess liquid or powder at the end of the process? This is especially important for any products that will be dyed after printing. If there is any excess material trapped inside, the product will not dye evenly, spoiling the overall effect. The exact size of these holes varies from material to material.
4) Is the file free of open edges and self-intersections? All edges should be closed, creating a solid volume in your 3D model. Make sure no internal geometry has been left behind by booleans and that all normals face outwards. It may be worth utilising an automated file repair tool to make completely sure all errors of this nature have been repaired.
5) Will all joints be strong enough to not break during the printing process? This is especially important for any weight-bearing or protruding parts. If your design incorporates a lot of joints like this, you will need to ensure that the chosen material will not break during the printing process. Also, consider what post-processing measures will be required. For example, if an air blaster will be used to remove any excess material after printing, this may be enough to break any fragile parts. In extreme cases, some modifications to the design may be necessary.
6) Has the mesh been subdivided in a way that will replicate any required smoothing modifiers? It’s common practice in 3D modelling to use a low poly count for the sake of speed, while using a smoothing modifier to replicate the effect of a high poly count and minimise render times. While this certainly makes the design stage more straightforward, 3D printers are unable to read smoothing modifiers. They should therefore be removed and the model’s resolution increased to create the desired effect.
If you incorporate this six-point checklist into your workflow for each additive manufacturing project, the chances of errors occurring during the printing process will be kept to the absolute minimum, while internal efficiencies are enhanced.