Additive manufacturing (AM), or 3D printing, is becoming a widely popular form of production. Although it comes with its own set of challenges, adoption of this process is accelerating. However, finishing, or post processing, for 3D printed parts remains a challenging task for most 3D part producers, including the medical, automotive, aerospace, and firearms industries. Bel Air has created a series of steps to help manufacturers create or improve the finishing of 3D parts.
In most cases, working with an expert like Bel Air is the best way to design a finishing process for a part. To get the most out of the experience, manufacturers should understand how the process works and how to measure the results of the process.
First, a 3D model can provide valuable information on how the part’s structure and size will affect post processing and help narrow down the machines, compounds, and media that can be used on the part. The 3D model, size, and geometry of the part will all affect the finishing process. For example, consider a large part with a complex geometry. Since there are many aspects associated with this geometry, the manufacturer should discuss background information on the part and its function with the customer. This will help decide which specific technologies to consider and provide vital information for creating a feedback loop to improve post processing.
The part may not be fully optimized for post processing – by suggesting alternative print layouts, post processing can be more expedient and productive. This step also aims to preserve and improve the cosmetic and functional components of the part. Once suggestions have been made and part design has been decided, manufacturers can consider the finishing needs of the part.
It’s important to consider the part’s purpose because it directly affects the details of the finishing process. Deciding whether a part’s finish should be for cosmetic and/or functional purposes is critical. Parts can be shiny, matte, or coarse along with several other surface qualities. The part can also be processed to a certain Ra value – a measure of the surface’s roughness. Additionally, manufacturers need to know how many parts they want to process a day and how consistent they want the process to be. In the mass finishing world, no two parts have the same exact finish – there are always slight variations. There will always be a few small defects in part processing, whether they come from printing or accidental wear and tear in post processing. Additional processes such as dyeing, coating, and electroplating can be done to improve the look and feel of finished parts. After all the criteria have been set, the parts are ready to be processed.
Sending a sample of acceptably finished parts can help create a more effective post process. Bel Air can analyze sample parts to determine their exact cosmetic and metric details using ZYGOT metrology data. Surface data is recorded using a contactless method, and a 3D image of the surface is created. Both provide an in-depth look into how surfaces can be improved.
After the part has been analyzed thoroughly, a sample process is determined based on the manufacturer’s needs, whether they are finish quality, price, and/or pure throughput. Machines, media, and compounds are recommended and selected for sample processes. Then, the processes are done and metrology is taken to determine the exact effects of each one. After this is completed, manufacturers should discuss the results and determine how to move forward. Additional equipment should also be considered to preserve machinery and media life and lower maintenance costs. More sample processes can be made, and manufacturer specifications can be changed in order to further improve or create a more realistic finish.