Hiya,
Not sure if there's a button I need to switch on somewhere in the settings, or if this is a bug.
Basically, F360s toolpath generator does a bad job wherever you have solid infill (i.e. surface layers) inside a concave feature (e.g. the bottom of a well.) Because F360 doesn't print a perimeter around the interior edge, the start/end of the infill lines are entirely unsupported and will produce a mess. (After 3 layers there's enough accumulated gloop that you'll get "a" surface but it'll be messy and full of holes.) In contrast, convex surfaces (i.e. those with an exterior perimeter around them) will print perfectly.
You can use this model as a simple example. The two 'wells' (left, and top-right), will have a horribly messy surface in the print. The surface at the bottom-right though will print perfectly.
This closeup of the generated paths shows the problem:
The lines of the surface fill are clearly starting and finishing in mid-air, with nothing to support them.
The solution would be for the generator to generate an internal permiter around the solid infill before filling it in. This still has a small risk at corners but on the whole it seems to work - for contrast, this is what Ultimaker Cura outputs for the same feature:
Note the additional perimeter line which is printed first, giving the infill something to hang on to.
If I missed a button in the print settings somewhere, feel free to let me know I'm an eejit; if not, please accept this as a bugfix! 🙂
