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Products => 3D printing => Topic started by: bostonman on September 23, 2021, 03:25:03 am

Title: Odd STL Issue When Using Support Material
Post by: bostonman on September 23, 2021, 03:25:03 am
In the attached contains a file name: Anet_A8_Y-axis_anchor_for_T20_pulley

I created the gcode and printed it, however, one side of the legs was thinner than the other. Initially I thought my printer aborted, but, when I looked at the stl file, I noticed this was how it was created.

If I remove supporting material, the part looks normal, but, when I add support material, I see a space exists between the legs (or forks - whatever you want to call them).

This space seems to be some void that is causing more support material to be printed and reducing the leg thickness.

Can someone look at it and tell me what's wrong because I've tinkered with numerous settings and can't solve the issue.
Title: Re: Odd STL Issue When Using Support Material
Post by: beanflying on September 23, 2021, 07:10:33 am
I get a couple of errors on the STL at the end of the upper arm. So depending on what slicer you are using run a repair on it and see if it helps.

Just for fun (and practice) I will see about repairing it and turning it back into a solid model in Fusion.

edit try this repaired one  :)

Title: Re: Odd STL Issue When Using Support Material
Post by: bostonman on September 23, 2021, 01:43:24 pm
I use a slicer called Slic3r and I didn't see a repair option (else I would have tried it), but will confirm this tonight.

I'm curious how a problem part made it onto Thiniverse without being caught all this time, but, a bigger question (just for my own knowledge): what caused that gap to occur?

I'm grateful it wasn't my printer that aborted because I recently upgraded to the latest version of Marlin - and I'm working on a leveling sensor. So I feared it was a bug in the firmware.
Title: Re: Odd STL Issue When Using Support Material
Post by: beanflying on September 24, 2021, 01:03:09 am
Download the Prusa fork of sli3er it is included. You can also transfer your setups across if you want to give it a run for slicing. I haven't looked at sli3er for some time as Prusa was driving the development well in front of the core so I just stuck with it.

https://www.prusa3d.com/prusaslicer/ (https://www.prusa3d.com/prusaslicer/)

Thingiverse as you are finding is a bit of a crapshoot when it comes to models. A lot of this is related to posting STL's instead of say STEP (fairly universal CAD format) and the conversion into those STL's by suspect means with no error checking. If over time Thingiverse was to stop allowing STL's would be a good thing IMO.
Title: Re: Odd STL Issue When Using Support Material
Post by: Infraviolet on September 27, 2021, 11:51:01 pm
Just a thought, and maybe the tools you've already got can do this better but:
have you tried importing the stl in to blender and using blender's 3d printing tools (an addon which can be enabeld in the preferences tab) to check for manifoldness, isolated vertices and distorted faces? it might catch meshing errors which slicers can't.