Solved How to get cura's time estimates closer to reality?

[widden 2]

I've tried asking this on reddit, but not much came out of it. I thought I'll try my luck here.

I've got an advice to install "printer settings" extension, which I did and set up, however it did not seem to fix anything.

I'm sure I'm doing something wrong.  But what?

 

Here's is the original post below.
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I've always been aware of a bit of a discrepancy in the estimate vs real time, and I can put up with it as long as it's not too bad. Eg ~30 minutes off on a 5-hr print I can live with.

However, it seems since I've upgraded my Ender-6 with a Biqu H2 and started building up speed, things have gotten a lot worse.

Latest one is an articulated snake, printing at 100mm/s walls & 150 infill; this was estimated to complete in 5:28 - took 2:56.

That's massive. 3 hrs vs 5:30 ! That's 50% extra estimated on top of the time.

Is there anything I don't know of? Is there anything that can be done to improve these estimates?

Interesting that putting the gcode file into https://gcode.ws/ results in an estimate of 2:28:49 - while this is under by half an hour, it's still a lot closer.

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And I've got a new one, since.
A test cylinder, a very simple thing, the project is attached.  Estimates 4:22 and takes 1:04. 

gcode.ws estimates 1:27.

I've attached the project for this.

 

Can someone please shed light on how to set up Cura to provide estimates a bit closer to reality?

 

 

TestCylinder.3mf

Edited April 3, 2022 by widden

[GregValiant 1,330]

In this case it appears to be something in the Settings Profile but I'm unable to find it.  Simply opening your 3mf file and slicing it I get a print time of 4:47.

Just switching to the Standard Settings profile (with infill adjusted to be the same as your settings) the print time drops to 3:09.  Switching the infill to Grid results in a print time of 1:54.

So maybe something is going on with that settings profile, or maybe with the Creality Ender 6 definition or the Creality Quality files?

As an experiment - try using a stock profile like Standard/Draft with 20% Grid infill and see if it makes a difference.

 

The Grid infill results in a few lines of gcode.  The Gyroid infill results in a bazillion lines of gcode because of all the curves.  Part of what is going on may be a cumulative error when Cura attempts to add up the print times for all those short line segments.  I have no idea if that may be true or not but in this case we can see that Grid v Gyroid makes a big difference.

 

This topic comes up a lot.  For myself, the Cura estimated time versus the real print time is consistently within 12% of each other and Cura always over-estimates.

 

[widden 2]

Thanks for looking at this.

 

I've now created a new profile, just copied the speed and accel settings into it, tried a few things and yes, they are indeed a lot more accurate now.   Nearly spot on.

 

Very interesting.

 

I'll simply on from this new profile.