Time Left

[DanielHolmSweden 15]

When I start print it could for example say, 23 hours left to print, after one hours it says 42, and later on 51! How come? And How can you estimate?

[gr5 2,265]

The algorithm could be much better.  Cura puts the estimated total time and the total number of layers in a comment at the top of the gcode file.

 

UM2 firmware (incorrectly) assumes each layer will take the same amount of time.  The firmware measure how long the layers have taken so far and how many layers have printed and how long the estimation is and tries to correct the estimation.  It shouldn't correct because the estimate from cura is usually spot on.

 

So if your print is for example pyramid shaped with a wide base and narrow top, then the printer will over estimate.

 

If your print is say like a table with many quick layers printing only 4 legs and then some very slow layers on top, the printer will under estimate.

 

Ideally cura should put an estimate of progress in a comment at the start of EVERY layer and the firmware should be able to compare that to actual time and update the estimated total time.  But it doesn't.

[DanielHolmSweden 15]

14 hours ago, gr5 said:

The algorithm could be much better.  Cura puts the estimated total time and the total number of layers in a comment at the top of the gcode file.

 

UM2 firmware (incorrectly) assumes each layer will take the same amount of time.  The firmware measure how long the layers have taken so far and how many layers have printed and how long the estimation is and tries to correct the estimation.  It shouldn't correct because the estimate from cura is usually spot on.

 

So if your print is for example pyramid shaped with a wide base and narrow top, then the printer will over estimate.

 

If your print is say like a table with many quick layers printing only 4 legs and then some very slow layers on top, the printer will under estimate.

 

Ideally cura should put an estimate of progress in a comment at the start of EVERY layer and the firmware should be able to compare that to actual time and update the estimated total time.  But it doesn't.

 

Edited May 16, 2018 by DanielHolmSweden
think it come in the wrong place:)))

[DanielHolmSweden 15]

Thanx for clear answer and with this I think I can with some maths figure it out:) / Daniel