strange impression problem

[caro 0]

Hello,

I have my Ultimaker 2 since a few days and I my printer is printing a vase in a very strange way as you can see on the next pictures:

 

The outside seems to be ok.

 

Has anybody an idea of what it can be?

 

 

 

[shurik 87]

Hi there,

An immediate thing to suggest is to mark the "Spiralize" setting in Cura Advanced Options panel. The wall thickness seems to be too much. 0.8mm would be sufficient.

What Cura version do you use? 14.03 gave me a rough surface most of the times. It was replaced by 14.04RC1 which is OK so far.

 

[gr5 2,178]

That's called stringing.

It's hard to answer your question without knowing more about your model. There are 2 types of vase or cup models:

1) Solid models where the model tells the slicer to fill the entire vase in with solid plastic - this is the easier to work with model as you can just check spiralize, set the wall width to around .6mm (if you go too think the nozzle can't handle it in spiralize mode because it does it all in one pass). One bonus of spiralize is that there will be no z-seam. Another is that there will be no stringing like this. Another option is to turn off combing. Combing allows non-retracting moves *inside* the part which is bad for you as the inside of this type of vase is visible.

2) Complete models that model both the outer wall *and* the inner wall. These complete models define the thickness of the wall (not Cura). These complete models will print horribly if you turn on spiralize. So if you have this type #2 of a model don't use spiralize. Instead you need to turn on retraction and make sure it is working by looking at your part in cura layer view. All blue lines are non-extruding lines but only the blue lines with a short vertical line at either end are movements that used retraction. Retraction is important to reduce the pressure at the print head to keep plastic from leaking out when you don't intend to extrude.

 

[gr5 2,178]

Also speeding up travel moves (Non extruding moves) to 300mm/sec might help.

 

[caro 0]

Thank you for your help.

Retraction was enabled. I use Cura 14.03.

My wall thickness is 1.2mm... which can indeed be too much.

The problem is not so much the fact that I have strings from one part to the other.

I was more concerned about the rough surface.

It stopped at some height.

I used a travel speed of 150mm/s, which can be too slow indeed.

It seemed (as Didier Klein pointed out on the french speaking part of the forum) that Cura adds some infill (although I chose 0%) which are yellow in Cura.

The good news is that you don't see it when the vase is finished as it only happens near the bottom :wink:

 

[DidierKlein 729]

Yes as i said in the french forum i noticed this behaviour on a couple of vases that i printed (without spiralize).

When you look at the layer view it looks like Cura adds some infill creating some patterns in the inner side of the vase. I'm guessing that the infill is added to make the print look better from the outside. But to me in most cases it's not needed.

Spiralize will certainly be more efficient in some cases. I'm just curious about water tightness of spiralized vases??