In order to reduce the size of a file, and therefore reduce the resources required to manipulate it in IronCAD, perform the following: go to TOOLS, OPTIONS and click the PARTS tab. De-select the option “exact surface description (Boundary Rep.)” under the heading “When saving parts, also save:”. IronCAD will now save only the history steps and the facet model, reducing the file size tremendously. The downside: each part will need to be regenerated before you can work on it. However, regeneration on each part only takes a few seconds at most so it’s really only a minor inconvenience.To “purge” unused data from an IronCAD file: Select the top assembly and go to File, Save As Part/Assembly, choose a new filename, de-select the “Save As Linked” option and click OK.