This article discusses some of the reasons why an IDF file, exported from CircuitWorks, may not match the original SOLIDWORKS CAD geometry. The IDF file format adheres to specific guidelines (see links below), and can cause an exported IDF file (created as .sldprt>Export to CircuitWorks) to deviate from the original .sldprt design. Since the IDF format does not translate to raw geometry, like a STEP file, please use the following guidelines in troubleshooting why an exported IDF file may look different than expected, upon being opened in CircuitWorks.
The documents available at the links at the end of this article outline the IDF format, which is one of the file formats used by CircuitWorks. The IDF format is an industry standard format for ECAD files, primarily for printed circuit board (PCB) designs. The IDF format has some limitations however, as the file type defines geometric entities/features with 2-dimensionsional data/mathematical definitions.
For example, creating a slotted hole in CircuitWorks using the .cwx native Circuitworks file type is possible, and as long as kept in .cwx or .sldprt file types, the feature will transfer from user to user/system to system without issue. Problems can arise when exporting/importing the same board design with the same slotted hole feature, but with IDF format (.emn/.emp file types) instead, as the IDF format can only translate the slotted hole feature into a circular hole feature defined by a center point and a constant radius, therefore creating a larger circular hole feature, not a slotted hole feature. The IDF format may also exclude/not recognize the feature altogether, as seen in the screenshot below.
***right-click on image >> select 'Open in new tab/window' for larger view***
This is a limitation of the IDF format, not CircuitWorks or SOLIDWORKS, as using other file types supported by CircuitWorks and/or SOLIDWORKS do not have the same issue. The specific slotted hole feature issue is documented in SPR 1035762 - CircuitWorks - Export to CircuitWorks - Slots are not exported consistently. Other issues regarding keep-outs or other IDF defined entities/features may not always be a limitation of the CircuitWorks application itself, but may be limitations of the IDF format. Keep this in mind when working with the IDF format for collaborative designs(MCAD/ECAD), and when working with your ECAD designer, as manual tips and tricks and design choices can be useful in avoiding these IDF translation limitations.
As far as choosing which IDF format version (1.0, 2.0, 3.0, 4.0) to use, Hawk Ridge Systems recommends using the IDF 3.0 format with CircuitWorks, as it most often allows for the best results. Here are two SOLIDWORKS Help links to documentation on the main differences.