geometrically it should be possible to build a filletSrf inside a surface, where the radius is less then the fillet radius.
@menno
a nice challenge for you …
_filletSrf R30 fails and crashes Rhino for the uploaded surface.
be carefull with playing around with _filletSrf, _offsetSrf _intersect _pull…
i crashed rhino several times with playing around with this issue…
innerSrfFillet.3dm (5.0 MB)
we miss some tools to handle those offsetSrf stuff where the offset is bigger then the smallest surface radius:
crash report:
{"app_name":"Rhinoceros","timestamp":"2025-09-14 23:58:25.00 +0200","app_version":"8.23","slice_uuid":"2aa841bf-e579-3ca1-86cc-f7e201278c7b","build_version":"8.23.25251.13002","platform":1,"bundleID":"com.mcneel.rhinoceros.8","share_with_app_devs":0,"is_first_party":0,"bug_type":"309","os_version":"macOS 13.7.7 (22H722)","roots_installed":0,"name":"Rhinoceros","incident_id":"4E932685-E941-464D-B178-BC19BCFAA397"}