Imagine you start with a cylinder and want to tilt that into the groove. Then the factor has to grow when radius or twist increase or when the height gets lesser. runsun wrote > What ratio did you infer to ? Can't figure it out from your code. -- View this message in context: http://forum.openscad.org/how-to-make-the-groove-more-width-tp20154p20184.html Sent from the OpenSCAD mailing list archive at Nabble.com.