Printing with Cheetah in Ultimaker 3 - Flexible filaments

[ana-mbh 0]

Hi community,

I have been printing with Ninjaflex and Cheetah during the last months, about 20 pieces or so, and it always worked well.

Last week I was printing with Cheetah, same settings as always and since the print was 18 hours I wen home (I have the printer at the office) then when I came back I found a huge mess!!!

It took me about 5 hours to clean the mess, there was cheetah even "inside" the print core, so I was heating the printcore and removing what I could with a lot of patience. I managed to clean it and it looked ok.

After that I printed Innofil PLA and ultimaker ABS, both with good results.

Today I printed with cheetah again, a small piece (35 min) and I printed it from a printcore AA in the extruder number 2, since it is cleaner that the one in the extruder number 1.

When I checked the printe it was printing ok, I left it alone for the last 10 minutes and...:

There is a point when it starts to just extrude material and it sticks to the noozle, the material is even having the nozzle shape:

I can see that the conditions change at some point, the part of the piece that I could save changes color after some good layers

Does anyone has a clue of the reason for this annoying thing!?? I can really figure out why this is happening now if I do things as I always did...

I hope someone can give some light to this topic...

Have a great day makers!