Internal Skirt for spiral vase and perimeter only

[studiokite]

I have been printing cone shaped objects with a spiral vase setting.

I would really like the skirt to be internal. Also then it would be hidden.

I have made my own in the models. S3d seems to have a hard time with less dense models and creates an incorrect number of skirts.

This generally means the object has poor adhesion and cracks free of the table.

I can get it close by manually tweaking the extrusion width.

I often see this problem on round objects and it can be quite hard to dial in the correct settings when doing a solid base for something like a cylinder.