Not sticking

[PAFablab 0]

Upon trying to print something a little harder than the Ultibot, (gyro by vitrox), my Ultimaker 3 is running into some problems. The PVA is not adhering to the print plate and during the start of the printing cycle the extruder for PVA (print core 2) deposits so much PVA material around the print core that it forms a mass or ends up dragging the material around as it tries to print. Can anyone help with this problem? 

[Brulti 129]

PVA is very sensitive to any kind of dirt or grease/oil on the glass bed, like fingerprints. Make sure that it is properly cleaned before you start your print. You have various methods to clean it: soap and sponge or Karcher's windows cleaner (the yellow one) works the best in my case.

 

The big blob of PVA at the start is also a known problem, if it's too bad, there's an option to disable it entirely in CURA. I'd suggest replacing it with a brim, both can serve the same function ie prime your extruder and make sure that material is flowing through before the printing really starts.

[PAFablab 0]

Thanks so much for your input! It helped a lot.