Is a slower outer perimeter speed still meaningful?

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In the past we had printers with poor mechanics and with primitive software algorithms, therefore we used to print inner perimeters faster than the outermost one. See for example (generic, found online):

enter image description here

However now we have pressure/linear advance which reduces extra oozing/extrusion in corners or areas with variable speed, and in Klipper we also have resonance compensation which takes care of imperfect mechanics allowing printers to be pushed to higher acceleration without visible artifacts (in my case from 2000 to 6000 mm/s^2), see (generic) photo:

enter image description here

However printing slower has a clear disadvantage: E steps calibration is speed dependent with more filament being pushed out at lower speed, see

Is there any reason left to print outer perimeters at a lower speed? Using one speed only except for specific areas (small perimeters, bridges, support) seems to make more sense to me to improve quality and reduce printing times.

FarO

Posted 2021-01-25T17:07:16.080

Reputation: 2 532

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Thank you for this question and all provided insight. I started experimenting with higher speeds after trying to answer question: Ideas to tune for 300 % speed. I observed big drops on start after long track's pressure-then-retraction, and had almost the same conclusion as a great explanation in the video. I manipulated flow rate to compensate, and slowed on last layers for nice finish. Actually the answer I proposed there reflects your way of thinking. So I upvote your question, curions to read from others.

– octopus8 – 2021-01-25T21:36:34.430

@octopus8 the implications of that video are quite far reaching... it is known for a while, but it has been forgotten. http://www.extrudable.me/2013/04/18/exploring-extrusion-variability-and-limits/ and https://forum.duet3d.com/topic/5588/non-linear-extrusion/6

– FarO – 2021-01-26T09:57:48.607

@octopus8 I replied to that question as well – FarO – 2021-01-26T10:30:40.123

No answers