Cura - Optimized Movement

[jeremyrichardman 0]

In 2.4 it appeared that Cura was by default optimized for movement in that when it was doing a layer change with multiple objects, it would not always move to the first printed object (and would instead go back over the objects in reverse order.

I cannot find where to enable that setting in 2.6, any assistance?

[jbloggz 0]

I'm currently running v3.5.1 and are wondering the same thing. I would much prefer if it printed multiple objects like this:
LAYER 1: 1, 2, 3, 4
LAYER 2: 4, 3, 2, 1

LAYER 3: 1, 2, 3, 4
LAYER 4: 4, 3, 2, 1

etc.

The way it currently works, when there are lots of little objects on the build plate, there is a massive travel at the end of each layer, which is not very efficient.

[burtoogle 513]

Since multi-threading was introduced to Cura, it always starts each layer in the same place (taking into account the shape of the parts). This is because it now computes the layers concurrently and not sequentially so the computation for layer N does not know where layer N-1 finished. Arguably, there could be an option to force sequential processing of the layers so that the unnecessary travels are avoided.

[eldrick 65]

The problem with the 1,2,3,4,4,3,2,1 sequence is that parts one and four are going to have two layers printed in sequence, and for small parts the first layer won't have time to cool before the next one starts, which often affects print quality negatively - it can leave globs on the parts at the beginnings and ends of the sequence.

Several slicers have used this sequence in the past, and most have stopped doing so because PQ is more important than time - it's a bug, not a feature…

[Shadowman 53]

1 hour ago, eldrick said:

The problem with the 1,2,3,4,4,3,2,1 sequence is that parts one and four are going to have two layers printed in sequence, and for small parts the first layer won't have time to cool before the next one starts, which often affects print quality negatively - it can leave globs on the parts at the beginnings and ends of the sequence.

Several slicers have used this sequence in the past, and most have stopped doing so because PQ is more important than time - it's a bug, not a feature…

Agreed 

[jbloggz 0]

I actually think the way it currently works is more likely to leave globs at the start of a new layer, because of the large travel needed.

I see now why things were changed for multithreading, but perhaps an alternative could be to process layers in pairs, so each thread gets two concurrent layers to process. This would allow it to start and finish each pair of layers in the same spot.

Either way, an option to toggle this behaviour would be nice, because I think most of the time there aren't any parts small enough to suffer from not being able to cool in time (at least certainly in the objects that I print).

Perhaps even someone could point me to the area of code that would need to be changed?

[burtoogle 513]

It's a shame that it can no longer start a new layer close to the position where the last layer finished but any large travels that are required to move from the end of a layer to the start of the next layer should not create artifacts if the retraction and travel settings are suitable for the material.