[Mysterious skin layer using Lines at 0°]

Oh - never mind - I think I found out it can be corrected with Enable Bridge Settings under the Experimental section.

 

 

[Mysterious skin layer using Lines at 0°]

(I am running Cura 4.3.0 so this could just be a bug that had already been fixed.)

 

I have attached a screenshot at layer 53, this is the top layer of an internal channel that cannot be reached so I placed a support suppression block over this area (I will be unable to fish out support from this channel).

 

As you can see, in the Shell section the Top/Bottom Line Directions are [] which should default to [45°,135°], and indeed does, for every other layer.

 

Yet on this first 'roof' layer over top of the partially unsupported channels, Cura unexpectedly changed to Lines at 0°.

 

(In the Shell section, if I change Top/Bottom Pattern and Bottom Pattern Initial Layer to Concentric, for example, this layer 53 still comes out Lines at 0°).

 

By the way, in the Experimental section I have Alternate Skin Rotation disabled.