Matter control Speed settings not understood

[Johncoffee]

I still ask myself why Mattercontrol uses so many different speeds during printing. While I think I understand the speed settings in MC pretty well - I don't understand the logic behind the speed changes in the sliced model. I have printed out my fan shroud again, because I've damaged (=melted partially) the first when turning off the fan during printing.
Here a screen shot of the settings and the sliced model.
Can anybody explain me what parameter
- decides at which speed most parts of the model are printed? (the green / light blue coloured one)
- why there is a change from green to light blue and green again at the lower side (~5mm height)
- why there is a change to 'yellow' at the upper wings area left and right
- why there is a change to blue again above the yellow area

I just don't get it.

Thanks in advance for any explanation on this.

*John*

[Johncoffee]

I think it has to do with minimum layer printing time, like 40sec. The print seems to be speed reduced at different levels. This explains some of the changes in speed.
But still I'm puzzled by the high speed at the bottom of the shroud. There the minimum printing time per layer doesn't seem to be maintained according the settings in the material...

[Xenocrates]

Because there is a lip there, it can go full speed, and where the lip goes away, it has to drop down in speed.

[Johncoffee]

Thanks Xenocrates for your feedback.
The different speed settings definitely have to do with the minimum layer printing time (cool down).
I think now I understood better how the slicer decides what speed to choose....

[cope413]

Yes, that is the correct reason for this part and the speeds "chosen".

In the future, feel free to email us - [email protected] - or you can "report a bug" through mattercontrol if you would like an explanation about the slicing engine or any of the settings.