Unwanted/useless retractions - Cura 2.5

[the_mechanical 0]

I printed a part preprocessed with Cura 2.5. When printing i realized a lot of retractions where i didn't expect them. When looking in Cura i found out why:

Between the inner and outer wall there is a done filling, but due to the small distance it is not possible to create something else than small lines - every one produces a retraction.

Thickness is 1.5mm, Nozzle 0.5mm

I thought about how i can remove this behaviour, but even increasing the wall thickness from 1mm to 3mm didn't help.

What i was wondering: The thickness of the area is 1.5mm - should be covered with the wall thickness AND 3x0.5 linewidth. Why not??? And why is the software making very short lines instead of a line thorugh?

That you can imagine: on the part are four such geometries, every causes about 20 retractions. This means about 80 retractions for these geometries on every layer, means for the 360 layers around 7200 extra/useless/unwanted retractions!!

Of course you can tell me - increase the retraction minimum travel or disable retractions. But with the used preferences i got good results, so i'll not change them.

Edited May 8, 2017 by Guest

[neotko 1,417]

Maybe is the infill overlap. Since that forces infill to touch perimeters, that might create small amounts of infill that the slicers needs to 'accomplish' the amount selected. If that's the case. Split the object in two, merge, and select per object setings to the part that doesn't need that.

[the_mechanical 0]

I understand what you mean, nevertheless the wall is done with 0.5mm and that does not fit to the 1mm which it should be. Where is the part of the "inner wall"??

And I'm as a user don't want to think about such special things.

So a request: would it be possible to give at least a warning if in a "small area" a lot of retractions happen? This would make one aware. In this case i realized it during printing. At generatig the gcode i never thought that this would be a problem - as said wall thickness 1mm should cover it.

Better would be that this never happens.