Circles not 3d-printing smooth

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SvenGoord
Posts: 17
Joined: Sun Feb 17, 2019 8:15 pm

Circles not 3d-printing smooth

Postby SvenGoord » Sun Feb 17, 2019 8:27 pm

hello, perhaps I should not have used daily version, but felt very brave. I cannot print smooth round items. In picture below ring with c is sliced with cura 3.4 printed on delta printer. Ring with red dots is sliced with slic3r printed on x-y printer. I searched and did not find anything, but changed segments per geometry to 250 and made no change.
not-circles-01.jpg
not-circles-01.jpg (76.73 KiB) Viewed 282 times
How do I get smooth circles? Thank you.

OS: Ubuntu 16.04.5 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.15860 (Git)
Build type: Release
Branch: master
Hash: 3b708c7f84b0425076b520e1d95627b20fd75fe0
Python version: 2.7.12
Qt version: 4.8.7
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)
Attachments
small-short-ring-01a.FCStd
(8.3 KiB) Downloaded 2 times
GeneFC
Posts: 1009
Joined: Sat Mar 19, 2016 3:36 pm
Location: Punta Gorda, FL

Re: Circles not 3d-printing smooth

Postby GeneFC » Sun Feb 17, 2019 10:04 pm

I looked at your FCStd file, and the shape looks a bit rough. It appears that you have the Tesselation at a coarse setting.

Look at Edit >> Preferences >> Part Design >> Shape view.

The "Maximum deviation . . . " in your file is set to 0.5%, which is pretty coarse. I keep mine at the minimum, 0.01%. It slows the computation a bit, but not a problem for moderate size files.

As an example, I added a circular object inside your ring. You can see the difference in smoothness. The original is magenta, and my addition is green.

Capture.PNG
Capture.PNG (7.88 KiB) Viewed 275 times

Gene
SvenGoord
Posts: 17
Joined: Sun Feb 17, 2019 8:15 pm

Re: Circles not 3d-printing smooth

Postby SvenGoord » Sun Feb 17, 2019 11:28 pm

GeneFC wrote:
Sun Feb 17, 2019 10:04 pm
It appears that you have the Tesselation at a coarse setting.
Thank you. I did not changed that. I updated it yesterday or the day before and that's when it start with the lumps. I didn't know what word to look for.

That seems to fix it on the screen and will print tomorrow to see. But looks ok.
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NormandC
Posts: 18534
Joined: Sat Feb 06, 2010 9:52 pm
Location: Québec, Canada

Re: Circles not 3d-printing smooth

Postby NormandC » Mon Feb 18, 2019 3:08 am

Hello SvenGoord,

Welcome to the forum.

GeneFC wrote:
Sun Feb 17, 2019 10:04 pm
The "Maximum deviation . . . " in your file is set to 0.5%, which is pretty coarse.
It's FreeCAD default.

When saving an STL file from the File --> Export menu, it takes the mesh representation used for the 3D visualization. But you can keep your shape view tessellation to a coarse value, and create a mesh from the Mesh Design workbench (menu Mesh --> Create mesh from shape). Then you can define a very fine mesh, and export this mesh instead.
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HarryGeier
Posts: 1112
Joined: Mon Jul 10, 2017 12:36 pm
Location: Hof Germany

Re: Circles not 3d-printing smooth

Postby HarryGeier » Mon Feb 18, 2019 7:46 am

I allways create the mesh from the mesh Workbench and then Export it.
I also allways use STANDARD Mesh.
Never had a similar Problem, regardless of Slicer used.
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SvenGoord
Posts: 17
Joined: Sun Feb 17, 2019 8:15 pm

Re: Circles not 3d-printing smooth

Postby SvenGoord » Mon Feb 18, 2019 7:38 pm

well is weird. I had friend send me similar ring.obj file in openscad. I slice with latest slic3r with both the freecad and scad files on bed to slice and print both at same time and freecad one still prints lumps, openscad looks ok and 3d skirt always prints smooth circle for both.

is there way i can get daily from one week or two week behind? Freecad is working ok until maybe one week not sure exactly but I check upgrade ever two days.
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NormandC
Posts: 18534
Joined: Sat Feb 06, 2010 9:52 pm
Location: Québec, Canada

Re: Circles not 3d-printing smooth

Postby NormandC » Sat Feb 23, 2019 7:45 pm

Since you're on Ubuntu, look into your /var/cache/apt/archives folder. It keeps previous versions of packages for almost a month.