I sometimes come across a very ugly UGLY message when I try to mesh. The description is especially misleading. Figure 1: Error! The problem is often fixable in SpaceClaim. Here's something to try: 1. Select everything (Ctrl-A), Right-Mouse-Button then Detach All . 2. Under the Repair tab, click on Stitch and click the green check mark to complete all. Hopefully the first step would solve all problems. You could verify this using the Check Geometry feature. It's not full proof but worth a shot. Figure 2: Check Geometry This would highlight any outstanding problem areas. Other repair tools such as repairing gaps and missing faces usually does the job. Otherwise, it may be necessary to get more fancy by removing the difficult surface by cutting it (Ctrl-X), then replacing it with blending or fill . A really neat trick with fill is Patch Fill. First click on Fill without selecting any geometry. Under the options, the default is Extend Fill . If any geo
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