Slic3r doing very weird thing (or was it?)

I'm running the 32bit version of slic3r 1.2.9 in windows 10.
It crashes more than anything ever.
That's not what I am asking about.

It seems to be happily missing parts off my first layer and therefore the rest of the sliced model too.

This is the model on the 3D view.


This is the gcode preview.


I am using settings that haven't changed recently.

Has anyone seen this before?
It also did this earlier with a model of a fan guard generated on thingiverse, it missed the bottom layer off the mesh in the middle of the fan guard as a result the next layer obviously became spaghetti.

Edited 2 time(s). Last edit at 09/21/2016 05:19PM by DjDemonD.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

you got netfabb installed? be interesting to see what it makes of the model

I ran it through the online version and it found no errors. Decided to cut the model in slic3r but it crashed every single time (there were too many to count) so loaded it in CAD and flattened it off at the base and it sliced okay. Having said that when I looked at it very closely in CAD the base of the model was flat, the centre section was not higher and even if it is it should still be present in the gcode preview, even if it probably won't print worth a damn.

I think what made me wonder if it was slic3r doing something odd rather than the model is that its the second fan guard I've sliced today that did the same thing.

I think it's probably that I've had two completely unrelated models, both with the same problem and therefore I've concluded it must be the slicer as the odds of two models having the same error from two different sources seem remote.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Does Slic3r complain that your STL isn't manifold?

Can you share the STL?

this last month I had no end of crashes with win10 and slic3r , then last week kicked win10 into the long grass, went back too win 7 and happy slicing so far.
thought netfabb may have thrown an error, as if those arm in the centre wasn't attached to the ring , kind of thing and slic3r ignored it.
you gonna share the stl. see if I get the same result here.

Edited 1 time(s). Last edit at 09/21/2016 05:39PM by jinx.

No complaints or autofix attempts. This is the original.
50mm_fan_prop_guard_v4_red.stl

Oddly the one I altered in CAD slic3r reports it has 25880 errors, but I just printed it no problems, and its now attached to my fan.

I was getting the same number of crashes in windows 7.
I might create a VM for slic3r and try it out a range of operating systems until I find the winning formula.

I have S3D but far from simplifying things it makes them much more complicated. Also I have not yet worked out how to have several printer profiles and switch between them in S3D.

Edited 1 time(s). Last edit at 09/21/2016 05:08PM by DjDemonD.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

Okay so ran it through netfabb again and this time its fixed it and it slices properly. Still not sure why it wasn't right in the first place though. Oh well.

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Simon Khoury

Co-founder of [www.precisionpiezo.co.uk] Accurate, repeatable, versatile Z-Probes
Published:Inventions

The inner ring and the next ring is not intersecting properly with the concentric pieces. The geometry overlaps which can cause problems during slicing.

My guess is you've skipped a boolean operation in the inner rings.

See the image below, the intersection on the left is correct, on the right is incorrect:

Fanguard problem

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Kind regards
Imqqmi

NFAN CoreXY printer:
[reprap.org]

netfabb lite didn't detect it, at first had to run the repair > detect.
could be worth checking for a slicer patch? for the crashes "I blame MS for the crashes, "

As far as the crashes go, I was having no end of trouble, and finally came across some builds of Slic3r that didn't crash.

[shop.prusa3d.com]

I use slic3r 1.2.9 in 64 bit Devuan Linux.

PLA: 1.75 mm
Layer height: 0.2 mm
Layer fan: on
3D Model: V29 Whistle in Thingiverse

Cura 15.x and Matter Control 1.5 produced printable gcode files.
Slic3r 1.2.9 produced flawed gcode files that shooting the diagonal arm in the air six or seven times.
It never managed to generate a printable gcode file of the whistle.


The nozzle did hit or dig into the layer and one diagonal arm was disconnected six times in a row.

Was the original design done using SketchUp?

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Ultra MegaMax Dominator 3D printer: [drmrehorst.blogspot.com]

This is the STL file I downloaded. [www.thingiverse.com]