SkeinPyPy: 100% infill on some objects

[destroyer2012 0]

I am trying to make this object

http://www.thingiverse.com/thing:7930

And what I get is 100% fill on every layer, some layers look like they have a bit of sparse infill but the layer directly above is 100% infill again. Seems like SkeinPyPy is messing up? This slices fine with slic3r.

Here is an example of what I'm talking about, from printrun's visualization.

I've tried changing the settings like fill density, etc. No difference. Other objects that are more square slice fine. For example this

http://www.thingiverse.com/thing:17768

slices and prints just fine, with sparse infill and everything.

Here are my settings:

 

[profile]filament_diameter = 2.889nozzle_size = 0.4machine_center_x = 100machine_center_y = 100layer_height = 0.2wall_thickness = 0.8solid_layer_thickness = 0.6fill_density = 20skirt_line_count = 1skirt_gap = 6.0print_speed = 50print_temperature = 0support = Empty Layers Onlyfilament_density = 1.00retraction_min_travel = 5.0retraction_speed = 13.5retraction_amount = 0.0retraction_extra = 0.0travel_speed = 150max_z_speed = 1.0bottom_layer_speed = 10cool_min_layer_time = 10model_scale = 1.0flip_x = Falseflip_y = Falseflip_z = Falsemodel_rotate_base = 0model_multiply_x = 1model_multiply_y = 1extra_base_wall_thickness = 0.0sequence = Loops > Perimeter > Infillforce_first_layer_sequence = Trueinfill_type = Linesolid_top = Truefill_overlap = 15support_rate = 100support_distance = 0.5joris = False

 

[Daid 306]

Funny, I noticed the exact same problem with one of my prints yesterday. Your posted settings do not match your print, but that's no biggy (support is exterior only, not empty layers only)

There are two possible reasons why SF could do this. One of them is because it thinks it needs to "support" the higher layers because of a steep angled side. The other because it thinks there is no layer above it, so it needs to make a "solid" top. You might think, why would it think there is a solid top? It clearly shouldn't think that. But SF is a bit... stupid. I've played with the "Surrounding Angle" setting in SF, and it didn't change the solid layers at all. So SF must be thinking it has empty space above/below it.

If it just finds a tiny ridge that would need support or solid infill, then it can fill the whole layer. Slic3r does this a lot smarter.

It might have to do with the huge amount of detail in the model (this will also give you buffering problems when you'll try to print). But I'm not sure. Slic3r gives a good GCode result. But doesn't generate support. BUT. The model might print almost fine without support. I'm still amazed what I can pull off without support some times.

[destroyer2012 0]

Funny, I noticed the exact same problem with one of my prints yesterday. Your posted settings do not match your print, but that's no biggy (support is exterior only, not empty layers only)

Hah, sorry I was messing around with settings a lot and i may have lost the proper file. You are right I set it to exterior only when I generated that gcode.

 

If it just finds a tiny ridge that would need support or solid infill, then it can fill the whole layer.

Perhaps if I increase the number of perimeters it won't do that... Upon closer inspection there really doesn't seem to be any overhang that fits your description. I changed the wall thickness to 1.6 mm and reskeined to see if that might solve the issue but it doesn't. Maybe wall thickness is counted differently than extrusion width when calculating whether to fill a layer? But even then, some layers are partially sparse-filled which skeinforge does not normally do, right?

 

It might have to do with the huge amount of detail in the model

I doubt this; the same thing happened on another, quite low poly model too. One similarity between that model and the lion is they are both organic-shaped (rounded over).

 

The model might print almost fine without support. I'm still amazed what I can pull off without support some times.

I might try it out. I was hoping to print another model that has this same problem; that one definitely needs support.

[Daid 306]

I just tried with 1.6mm walls. And I noticed something odd. It doesn't add more then 1 perimeter line for the layers with the "odd infill".

As a test I also sliced with 0.5mm layers, which made the problem worse instead of better. I'm also seeing places with SF should have put "support infill" but hasn't. It's an odd problem.

[destroyer2012 0]

Any insight at all on this? I know there are some people that have printed organic-shaped objects with support. How in the world do you do it?

[tinsoldier 1]

I had similar issues on Cura RC2/SkeinPyPy when printing this yoda

http://www.thingiverse.com/thing:14104

Per your comment Daid, I had also tried it with zero infill and thicker walls and ended up with same issue with single perimeter walls on all the layers where it *was* doing the solid infill.

Just chiming in hoping the info will contribute to the problem solving.