Hi Ad,

Re:
> I get the short visible (red) segments even if I
> uncheck the "create hidden lines" option.

My experience is that these sort of lines are unavoidable. They get shorter as canvas megapixel resolution is increased, so I usually use 200 which is limited by the RAM I have, but I've never figured out a way to eliminate them entirely. They seem to happen wherever a hidden radiused surface like a hole or a fillet meets a visible surface.

I just delete these fragments manually one at a time since where they occur is predictable.

- Peer