Cura 14.03 combing fail?

[Nicolinux 288]

Hi,

I wanted to print this model (link) at 0.5 scale with combing enabled. Looking at the layer preview there are travle moves which do not respect the layer boundaries.

Isn't combing supposed to travel only inside the model? The "inappropriate" travel moves correspond with ugly bumps on the printed model (even when printed at 20mm/s and 200°).

 

[Dim3nsioneer 557]

It's the same effect with 14.03-test2... Maybe combing moves are limited to a certain number of G0s? If it cannot be done within this number, it's just following a straight line?

 

[Nicolinux 288]

I have just tested it with Cura 14.01 and it is the same there.

 

[illuminarti 18]

I'd think you get better results by turning off combing, and just letting the printer retract properly on those moves.

 

[Nicolinux 288]

Yes I can do that. Just wanted to highlight a possible bug in Cura.

 

[Daid 306]

Actually, these results are expected. The areas where no combing happens are so thin that combing would have a bad effect on the outside skin quality, as the nozzle would be traveling too close to it. So it retracts and travels. (You can see the retraction marks on the preview)

 

[Nicolinux 288]

Sounds resonable. Thanks for the explanation Daid.