The designer had previously drawn a center guide line across the top face (to align leg holes). That guide line was a hidden, un-deleted edge. The Round Corner tried to round across that internal edge, creating a crack.
Why does this happen? More importantly, how do you fix it without scrapping hours of work?
: While previously free, RoundCorner and its successor, FredoCorner , are now paid extensions requiring a license from SketchUcation . sketchup round corner crack top
Give you a step-by-step method to clean up "reversed" (blue) faces using the Default Tray.
: Close the component. The original, small version will have inherited all the new, clean geometry without the cracks. 2. Check for Non-Planar Faces The designer had previously drawn a center guide
Creating smooth, filleted edges in SketchUp is essential for realistic 3D modeling. However, plugins like or FredoCorner can sometimes cause geometric errors. One of the most frustrating errors is the "crack top" phenomenon, where the top face of your geometry splits, tears, or develops open gaps after rounding an edge.
The crack appears when the plugin fails to triangulate the cap correctly. The primary causes are: Why does this happen
The issue is rarely a flaw in the plugin itself. Instead, it's a sign that your model is hitting one of SketchUp's core geometric limitations.
Trying to use cracked versions of paid plugins is extremely risky. Malicious actors often embed viruses or keyloggers into sketchy activation tools found on shady sites. Even if you ignore the security risks, cracked plugins rarely work correctly with modern versions of SketchUp and will fail to update.
Here are the most common reasons this happens and how to fix them.