wall thickness, model thicks & filling

[vincentp 0]

another topic about this, I apologize if it's a duplicate, I've search for recent topics matching my question and couldn't find any.

First off, I'm very happy with my UM, I've been struggling a lot at the beginning with both SW setup and understanding parameters, and some HW issues (I have the first gen UM and needed to upgrade both extruder and drive).

Now I've reach the "click and print" situation which I'm so happy with, get a model on thingiverse or design something, slice with the profile of my choice, put on the SD card and print, I get consistent results.

now for the question : When I was trying to get different results with wall thickness and filling density, I realized cura had troubles filling certain areas.

From what I understand, cura uses the wall thickness value ALSO for the filling pattern, so if you have a thick wall value and a thin contour, cura will print the outlines but won't fill with anything.

you can off course make the wall thickness smaller (I used 0.8 initially and tested 0.4 mm) but then the quantity of material for filling is much less and it doesn't look as "filled" a with 0.8, density looks affected by that.

The classic example is a drilled standsoff. If the OD is 5mm, wall is set to 0.8 and the center is drilled (empty I mean) with an ID of 3mm, you get 2 outlines of 0.8 which = 1.6mm then the remaining gap inside the 2 outlines is 0.4m and cura considers it can't fit anything there. As a result, you get 2 cylinders, one inside the other, and they are unconnected.

I've tried with cura 12.12 and 13.03. I've been told I should use another slicer, like kisslicer (?) but I don't see myself getting into learning again all the parameters and testing forever PLUS I love cura.

is there a way to tell the slicer to fill those gaps. I mean, I can think about walls and thickness when I design a model eventually, but if I print something designed by someonelse then realize it has failed after 45 minutes of printing, that's not good.

maybe the new version of cura (different slicer) improves this ? happy to hear your experience with that issue.

thanks !

 

[Daid 304]

The new 13.05 beta improves this, as it fill fill up the gaps that are left empty in the old version.

 

[gr5 2,069]

This is sometimes referred to the "thin wall" problem although some people say the "thin wall" problem is something else (where the wall is so thin that Cura prints *nothing*.

Anyway I recommend you get the beta as daid says. It's here:

http://software.ultimaker.com/Cura_closed_beta/

It seems to be working pretty well so I think it's relatively safe.

The other option is to lie about your nozzle thickness. So in your example the wall of the cylinder I suppose is 5mm-3mm/2? That leaves 1mm. So cura does a "perimeter" aka "wall" pass twice at .4mm each and that leaves .2mm to be filled. The new beta will fill that but cura won't. So instead tell Cura (13.03, not 13.05) that your nozzle thickness is .33mm or maybe even .3mm and it should make two perimeter passes and a fill pass. Look at the gcode graphically with cura before printing to make sure it does it right.

I assume you also have to set the wall thickness equal to the nozzle size. I haven't played with this much myself.

One would think lying about the nozzle size would cause other problems but people have said if the lie is small enough (from .4 to .3 is 25% change) then you will be okay.