UM 2 Ext: air gap in prints - prints starts OK, but then the platform is lowered too much

[popdog 0]

Hi forum!

I just got my Ultimaker 2 Extended and did some test prints and faced some problems...

I tried to print the "cup with lid" (https://www.youmagine.com/designs/cup-with-lid) with different print quality settings. At draft mode (0.2mm layer) and normal quality (0.1mm), it printed just fine. Then I tried the maximum quality settings (quality slider in cura basic mode to the right). The print started without problems, but after a third of the print a gap was produced and the extruder began to print in the air.

After that I tried to print the Elephant by FabShop with the print settings from this youtube video:

(Scaled up a bit, 0.2mm layer thickness, raft). The raft was printed correctly, but then the build platform lowered too much and it printed in the air again.

The UM stands steady on a solid table and there were no vibrations during the prints.

I'm using PLA (the silver filament came the UM).

I attached two photos.

Does somebody know whats wrong?

[popdog 0]

A little follow-up:

I updated the firmware to the lastest version (_15.04.02ex) and tried to print the elephant again (same gcode from same SD card). This time it came a lot further, but the same problem appeared.

[Dim3nsioneer 444]

standard firmware? Which version?

[popdog 0]

Standard firmware, version 15.04.02ex

Updated using Cura 15.06.03

[Remy 13]

Standard firmware, version 15.04.02ex

Updated using Cura 15.06.03

 

I've had reports of 15.06.03 still causing issues. You can also revert to 15.04.2 Cura (legacy version) which is basically the same and a bit more stable as far as I can tell. You can download 15.04.2 here: https://ultimaker.com/en/cura-software/list

I would also look at the model in layer view in Cura to see if the gaps are present there as well. I'd also recommend looking at the gcode itself in a free gcode viewer like the one here: http://gcode.ws/

If the gaps appear in the layer view in Cura or with the gcode viewer then it is a problem with the slicing engine not outputting correct code.

If not then it could be a mechanical problem. Are you sure that you're not just getting some under extrusion? How far does the build plate lower (approx)? In the first photo of the cylinder model it looks like it only missed a couple layers, which could be caused by under extrusion as then it picked back up again ok. Under extrusion looks like the photo in the guide below:

http://support.3dverkstan.se/article/23-a-visual-ultimaker-troubleshooting-guide#underextrusion