: Right-click the first part and use an extraction tool like WinRAR or 7-Zip . This will produce the actual CAD file (likely in .STEP , .IGES , .SLDPRT , or .DWG format). Phase 2: Create the Solid Feature

Once the file is imported into your CAD software (such as AutoCAD, SOLIDWORKS, or Mastercam), use one of these common methods to establish it as a solid:

: If you have a collection of surfaces that perfectly enclose a space without gaps, use the SURFSCULPT command to convert that "air" into a solid body.