Cura Experimental Feature in the post script

In the post processing script of the cura slicer, there is a feature called At Z5.3.0 (experimental). Does anyone knows how to use this? I have try to use it several time but it doesn’t seems to get called or activated. I am trying to change the speed of my printing according to layers. The top layes with details at a very slow speed as well as the 2 bottom layers but the rest of the thickness would be at a fast print speed. I am not aware of any other way to do this in cura. Any suggestion would be appreciated. Thank you

Change At Z5.3.0 allows you to alter a limited number of print actions. As it turns out speed is 1 of those features. I’m going to post a series of screen captures that I hope will help:

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I assume you have found this window and clicked on the ChangeAtZ item.

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Not sure what you’ve done in this window. I always change Trigger from Height to Layer No. Then I enter the layer number where I want things to change.
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Here’s an example of sample values. This will cause the speed to change to 150% starting at layer 5.

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Now, this may be where you’re getting confused. I know it confused me at 1st. In your case, you may be wondering how you get the speed to slow down again. The answer is that you add the same ChangeAtZ feature a 2nd time, so you have 2 of them in the window. Change the values in the 2nd entry to what you desire.

You keep adding the feature as many times as required to satisfy all the changes you want to make.

I hope that helps. Oh, and don’t forget to remove the ChangeAtZ after you’re finished with that model. If you don’t, it will be used for every print you make in future.

Very Good explanation thank you so much for your thorough answer. did you notice that it actually works and the speed does change accordingly. Is there a way to query the speed to verify ? maybe with a Marlin commands?

There may be a gcode command to query speed, but I don’t know it. You can look at the gcode file and see if the speed changes at the layer you specify, but I’m assuming you’re not at that level quite yet.

1 way to do it would be to create a small square that’s 0.4mm high. In Cura, I would specify the height as 0.20mm and the speed as 20mm/sec. After slicing, I would ensure that the model has 2, and only 2, layers. In Post Processing, I would add a ChangeAtZ and set it to change the speed at layer 2 to 300% or higher.

Next, I would ensure that there is no filament in the printer. I would heat the nozzle to 180C (to ensure a “temp too low” error doesn’t occur). Then I would print the square. I would look for slow movement of the nozzle during the 1st layer and the nozzle to speed up significantly for the 2nd layer.

Try activating the “output to display” just under the “Apply to” . in the same list of choices you are setting.

Ok yes. Great idea. Thank you so much.