Additive manufacturing

Introduction 3D metal printing

In this web text we would like to give you a few rules of thumb and tips to quickly and efficiently obtain a clear and comprehensive price offer for 3D metal printed parts.

 

Design for 3D printing

Perhaps the most important rule; always keep the technique of 3D printing in mind while designing. This greatly increases the chance of obtaining a good printable part. Design for 3D printing…

A drawing can be supplied as a CAD file such as STEP or as an already 3D print-ready STL file. To avoid misunderstandings with dimensions, it is recommended to send a PDF-drawing with dimensions. This way, the dimensions can be checked and scaling errors can be detected at an early stage.

A common ‘mistake’ made by designers and engineers is requesting a quote for 3D printing a design that is specifically drawn for a machining operation. Having a lathe or milling design 3D printed is not a good idea at all. Just like turning, milling, injection molding, wire EDM … 3D printing has its own design principles. If these design principles are not followed carefully, there is a good chance that it will not be possible to print the part. In addition, the cost price will most likely be too high. The next page explains how a 3D metal printing price is established. There are some factors that can make a 3D printing price rise quickly, so it is important to take these factors into account.

 

Unnecessary volume = unnecessary costs

With 3D printing techniques, material is always added layer-by-layer. This is completely opposite to subtractive machining where material is removed (machining operations, milling, turning…). It is therefore important to avoid unnecessary material as much as possible. The less material (metal powder) that has to be printed, the less machine time and the lower the cost price per piece.

How to reduce the volume of a 3D print? Some methods at a glance:

  • Removing unnecessary functionalities
  • Choice of material and reducing wall thicknesses (if titanium is used as a printing material, the wall thickness can be reduced by 50% compared to, for example, a material such as aluminum).
  • Use mesh structure instead of solid material. Mesh structures can be quickly applied to fill the inside of a component. Often a honeycomb structure is used, which provides the highest strength with the least mass. Using mesh can make a huge difference in weight and volume. Relatively easy to apply with CAD and slicing software (Netfabb, Grasshoper, Magics …)
  • Topology optimization
    • Computer calculations make it possible to quickly create a topologically optimized redesign of your drawing. The software takes into account the material used, strength calculations, form determinations, construction direction, constraints … A topological design is quickly recognized by its organic design. Topology optimization is an excellent way to obtain lightweight and easily printable parts. Advanced design level required. However, fusion 360 Generative Design is a low-threshold recommendation.

 

Avoid unnecessary support structures

Finally, try to create a 3D print design that requires as little post-processing as possible.

  • Respect maximum overhang (45 °). Above 45° support material is necessary. Support material must be removed, this requires machine time and man hours.
  • Try to design as many self-supporting structures as possible
  • In short, follow design principles 3D metal printing.

Detailed design guidelines for 3D metal printing can be requested via – also available by telephone for further questions concerning “introduction to metal 3d printing”.