Filament drops on the last Layers / Gaps

[michaelmi 0]

Hello,

 

I bought my Ultimaker not long ago. Printing was nice, but now I have the first bigger problem. I want to print horizontal surfaceses with round 10 - 20 percent of filling, to save material.

My problem now is, that the upper layers (above the support) weren't filling the Surface out.

My Printer tryes to print straight above but the Filament drops down everytime. After the fourth layer the surface is getting better but still not good. When the Print is finished there are some holes in it.

I tried to change some parameters like speed, temperature, fan, and material too - but I didn't get acceptable results.

 

Can anybody help me please?

 

[IRobertI 429]

Make sure your fans are going full blast and increase the thickness of the solid top a bit so that more solid layers are put down.

 

[michaelmi 0]

Hi IRobertI!

thanks for the fast post!

the fans are on full blast.. and i know that increasing the thickness could solve my problem, but I don't understand that when my printer prints with brim there is no problem. The Printer prints nice when he's making the brim. I don't see any big differences between making the brim and making the upper surface (at bridging). And when i see that someone is making a bridge challege with lenghts up to 10 cm i dont understand..

What I want to say is there must be a other solution to solve this, isn't there one?

 

[IRobertI 429]

What settings are you using? Very thin layers have a harder time to bridge properly. Fast print speeds can also affect bridging in a bad way.

The issue you're having is what we call "pillowing", and rather than repeat myself I'll link you to this page instead

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

 

[michaelmi 0]

I use the folloing settings:

layerheight: 0.1

speed ~70 mm/s

temp: 235°C Bed: 110°C (ABS)

temp: 220°C Bed: 40° (PLA)

Fan up to 100% (at top surface)

bottop/top thickness 0.4 mm (But I will set this up to 0.6-0.8)

Thanks for the link to troubleshoot page and for the tips. Ill try to do this at weekend!

 

[Dim3nsioneer 377]

With the brim you change the thermal airflow induced by the heated bed. Best solution certainly is to increase bottom/top height as Robert suggested.

Alternatively you may try to put some cardboard or similar around your print when some millimeters are printed to block the thermal airflow and check if it makes a difference.

 

[gr5 962]

The thin strings of filament at .1mm layer aren't thick enough and break easily. Also they tend to be underextruded at the beginning of movement. Print the top layer much slower - say 25mm/sec. Printing slower will allow you to have a more consistent extruder flow (because your extruder isn't slowing down and speeding up at every new line). Or use .2mm layers.

If slowing down helps (I'm sure it will) you can use a plugin which changes the speed near the top of the print.

Also some brands of PLA don't break as easily.

Also triple check your fans. If only one fan is working or if they are sucking instead of blowing, then this kind of hole in the top is common.

 

[visu-al 2]

bottop/top thickness 0.4 mm on a layerheight of 0.1 is really not enough !

to make a nice top layer you need at least 5-7 times the layerheight, yours is only 4 times wich is just not enough!

0.1mm X 7 = 0.7mm bottom/top thickness you would need to make it solid top filled when using full power fan..

 

[michaelmi 0]

Ok I'll try this at Weekend. I Thought it should be possible because of the bridge challenges..

So thank you all for the quick answer!