Control the Quality of STL Data

The integrity of the source model has a direct bearing on the quality of the data produced during an STL export operation. For example, if a solid in the original model is not properly closed prior to being exported, then ImPLANT-STL will not recognize the resultant triangular facet group as a single primitive and will map the solid inefficiently with POHE primitives. Most Mechanical CAD Systems have a healing facility that will process the model and check it for inconsistencies such as solids that are not properly closed. It is therefore strongly recommended that source models are healed in their originating Mechanical CAD System prior to the data being exported in STL format. Where the Mechanical CAD System does not have this facility, another application such as CADfix may be used to provide the healing function and to carry out the export to STL format.

The STL format is an approximation of a curved surface model, the accuracy and level of detail of which may be controlled through tolerance setting. A balance must be struck between too great and too low tolerance settings. This can be done by reviewing and where necessary improving the model created.

• Too great a tolerance setting may result in errors in the STL file.

• Too low a tolerance setting may result in the STL translation operation failing, eg where holes are located close to the edge of a solid.