Cases
Fast and accurate MPA analysis on optimised STL models!
Cutting time and costs while improving product quality - that's the biggest challenge in product development nowadays. Finite Element Analysis (FEA) applications enable designers to rise to this challenge by detecting problems and optimising designs at an early stage. This drives efficiency, cuts costs and results in a competitive advantage. An example: RapidParts, a successful rapid tooling site, can realise very short lead times, partly because they analyse all parts with Moldflow Part Adviser (MPA) software. By using Magics, RapidParts is now able to take full advantage of MPA analysis.
"Garbage in - garbage out"
We receive STL files from various sources and unfortunately some are of low quality. Consequently, these files don't run in MPA or return incomplete analysis results. In those cases, problems can be overlooked, causing costly delays in production. To eliminate this, we looked for a way to improve the quality of STL files and thus maximise the quality of the analysis results. We found the ideal solution in Magics.
RapidParts engaged in a study to find out if STL file quality influences the quality of MPA results. A random sampling of 100 recent tooling projects was analysed with MPA. It revealed that the 'garbage in, garbage out' rule also applies here. Low quality STL files - those files that don't meet all MPA's requirements for STL files - proved to be the files causing problems in MPA. 9% of the examined files crashed in MPA and 3% returned an incomplete result.
Easily meeting all MPA quality requirements with Magics
Next, RapidParts looked for an easy way to increase STL file quality. With Magics, they found the solution. Magics software offers automated tools to repair and optimise surface meshes so that they meet all MPA quality requirements. (For a detailed overview, take a look at the table).
| MPA requirements | Magics tools |
| 1. Complete & incorrupt STL file | Wide range of automated fixing tools |
| 2. STL file: ASCII or binary format | (This is standard in Magics) |
| 3. One solid | "Unify" function - "Shells to parts" function |
| 4. Triangle normals indicating the "out" direction | "Flip normals" function |
| 5. Orientation of triangle normals: aligned | Wide range of automated fixing tools |
| 6. No gaps or free edges | "Stitch" function - "hole filling" tools |
| 7. No intersections between triangles' surfaces | Self-intersection detection - "Unify" |
| 8. No triangle overlap | Detection of double surfaces |
| 9. No more than 100 000 triangles / model | Triangle reduction |
| 10. Triangles: aspect ratio less than 6:1 | Tools to increase the triangle quality aspect ratio (=surface mesh optimization) |
Fast and accurate analysis for every STL model
RapidParts routinely uses Magics to repair files before running them in MPA. Since they started using all available Magics tools (including checking for intersections and improving triangle aspect ratios) they've obtained a 100% success rate with MPA.
By using Magics' different STL optimisation tools, we obtain a wider range of results, since all files can be fixed and prepared for MPA analyses. The results are more accurate and complete because the mesh meets MPA quality requirements. We also save time, because better STL surface definition and triangle reduction allow faster calculations.
Study of 100 tooling projects reveals more accurate and complete MPA analysis:
When improving STL file quality with Magics' repairing and surface optimisation tools:
- Success rate: 100% (no more failures!)
- Average time savings: 16%
- Average reduction of the number of triangles: 23%
