PrusaSlicer Bridges Parts when Gap is small

[jimvb-ut]

Version

                    Prusa Slicer Version 2.2.0

Operating system type + version

                    Windows 10 Pro - v1909

3D printer brand / version + firmware version (if known)

                    Original Prusa i3 Mk3S-MMU2s

Behavior

                    BUG -- Prusa Slicer Completely ignores Perimeters when gap between parts is small.  Slicing Planetary Gear Bearing with small tolerance (to make the Bearing less sloppy) causes bridging between the Planet gears and the Ring gear (see screen prints) - this is in the Slicer and NOT a printer problem.

                   This is even more obvious when slicing the Makers Muse Tolerance Test v3.0 STL file.  The 0.05 mm test plug is completely incorporated into the base. (see screen prints).

                   These problems ARE associated with the Prusa Slicer.  I have tested the same files with Cura (v4.61) and these issues are not present in the sliced file.

                    I fully realize that the Printer may not be able to successfully print these Models, but that is the whole reason to print the Tolerance Test and if I use the Prusa Slicer I will not get a valid result because the smallest gap is solidly attached

Project File (.3MF) where problem occurs

Makers Muse Tolerance Test v3 - 3mf.zip

[neophyl]

If you go to Print Settings>Advanced>Slicing in either Advanced or expert mode you will see a setting called 'Slice Gap closing radius'. By default it is set to 0.049mm.

This setting is designed to fill in small cracks of the model. If you read the tooltip it fills in gaps 2x the closing radius. It is this setting casing the slicing issue. I added an extra couple of zero to make it 0.00049 and it then slices without a problem.

Just edited as I see the default is 0.049 which at 2x will close an 0.05 gap.

[jimvb-ut]

Wow! Thank you for responding so quickly. So this is a Feature - not a bug. Thanks for pointing this out to me, I don't think that I ever noticed this setting before. This works as you say, and slices correctly when I reduced the 'Gap closing radius'. However, for some reason my copy of Slicer seems to think that the default value is 0.049 instead of 0.0049 as you stated above. Actually the 0.0049 value seems sufficient for my needs right now. Anyway this works. Thanks again. Jim von Behren

…

On Fri, May 15, 2020 at 1:01 AM neophyl ***@***.***> wrote: If you go to Print Settings>Advanced>Slicing in either Advanced or expert mode you will see a setting called 'Slice Gap closing radius'. By default it is set to 0.0049mm. This setting is designed to fill in small cracks of the model. If you read the tooltip it fills in gaps 2x the closing radius. It is this setting casing the slicing issue. I added an extra zero to make it 0.00049 and it then slices without a problem. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#4245 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/APSYYDSHL2RSR4XAJNEMQMLRRTSGPANCNFSM4NBFGCEA> .

[neophyl]

Yeah sorry I miss read the value and it was only after posting that I noticed which is why I edited my post.

[bubnikv]

Solved, closing.