The Cura's estimated print time is not accurate.

[Carina0810 0]

Hello friends,

 

I bought a 3D Printer from the third part, and I found the actual print time is much longer than the Cura's edtimated print time.

 

How to make Cura's print time accurate without affecting the Printing quality?

 

[Smithy 1,146]

Cura can give you only an estimation and it can differ from the real print time. You could check the travel speeds and such things and adjust the speeds to your limits in the printers firmware. But the question is, if it is worth just to come closer from the estimated time.

 

I guess that Cura uses higher travel move speeds and calculates from these speeds. But the actual speeds are limited in your printers firmware and therefore the actual print is a bit longer than the estimation.

 

The estimated print time has nothing to do with the print quality.

[Carbon 28]

I find it fairly accurate.

 

When I begin prints, I check the first few layers.....once the print  is well underway, I always "Tune" the print speed to 130% - 140% as it's a nice surprise to come back to the printer and it's almost finished, sooner than expected.......seems to work ok with PLA, not too well with ABS mind (delamination of layers...)

[GregValiant 1,351]

 

Cura's time estimate is based on things it knows.  You've told it the print and travel speeds and maybe you've entered the Acceleration.  Then the gcode gets to the printer.  The printer might have limits on Speed and Accel that Cura can't be aware of and so the estimate can be far from accurate.

(PLEASE NOTE:  The following only works on printers that accept the M117 command.  That excludes some Creality printers with 4.x.x boards.)  Since it is a post processor it has no effect on the time you see near the slice button in Cura.

 

One of the Cura contributors wrote the attached post-processing plugin.  It has a couple of options and one is a "Fudge Factor" for print time.  (I prefer it to the Display Progress plugin which has no fudge factor.)

By comparing the actual print time to what Cura is saying it will be, that Fudge Factor can be adjusted to:  Cura Print Time (in seconds) / Actual Print Time (in seconds) = Fudge Factor.  Mine came out to 1.1.

;TIME:3900  ;At the beginning of the file.

;TIME_ELAPSED:85.912422  ;The time to print "LAYER:0"
;LAYER:1
M117 2/100 | ETA 57M

M118 2/100 | ETA 57M

The M117 line sends the info to the printer LCD (I added the M118 line to bounce the info back to my print console).  The layer number coincides with Cura rather than with the gcode file.  In the case above the ETA was calculated with my 1.1 fudge factor.  The LCD would show "2/100 | ETA 57M".

 

Extract ShowProgress.py from the attached Zip folder.

Copy the ShowProgress.Py file into your Cura program folder "...\plugins\PostProcessingPlugin\scripts".  The next time you start Cura it will be available to add under "Extensions | Post Processing | Modify Gcode | add script".  Alter the Fudge Factor as required and the time displayed on the LCD will be somewhere closer to reality.

ShowProgress.zip

[DivingDuck 105]

On 6/24/2021 at 7:43 AM, Carina0810 said:

I bought a 3D Printer from the third part, and I found the actual print time is much longer than the Cura's edtimated print time.

 

How to make Cura's print time accurate without affecting the Printing quality?

 

 

Look for plugin "Printer settings" by fieldOfView at Marketplace. It will give you access to your hidden printer settings in Cura. Compare the values with your printer firmware values. Guess, this will give you an explanation why there are bigger differences.

Usually there are some default setting values  in Cura for acceleration and speed that are wrong.