Support when using adaptive layers

[12nh 0]

Weird support when using adaptive layers
Isn't this a specification?
(google translate)

Ultimaker Cura 4.12.1

Edited January 2, 2022 by 12nh

[Smithy 1,146]

Please post your messages in English, otherwise we cannot read and answer your topic. Thanks!

[12nh 0]

2 hours ago, Smithy said:

Please post your messages in English, otherwise we cannot read and answer your topic. Thanks!

I'm sorry I didn't confirm enough

[GregValiant 1,355]

The "Overhang Angle" is calculated according to line width and layer height.  It is the angle of a line running from the lower left corner to the upper right corner of the rectangle that portrays the area under the nozzle.  When the layer height is less, that angle is greater and when the layer height is greater then that angle is less.

Since using adaptive layers causes the layer height to bounce up and down then the calculated "angle requiring support" changes.  When the layer height is uniform throughout a print, then the angle doesn't change.

 

In the image below - the cartoon on the left shows two 0.2 x 0.4 rectangles just touching at their corners.  The theoretical maximum Support Angle is 63.4°.  If an actual model has an angle above 63.4° then the extrusion on top will absolutely not be in contact with the extrusion below and you are air printing.  When the layer height is lowered to 0.1 then the theoretical maximum increases to 76.0°.

 

Now the actual question becomes "Is this the way it actually works in Cura" or is it just a "geometric/trigonometric anomaly" and my reply to that is - I have no idea.

 

[12nh 0]

2 hours ago, GregValiant said:

The "Overhang Angle" is calculated according to line width and layer height.  It is the angle of a line running from the lower left corner to the upper right corner of the rectangle that portrays the area under the nozzle.  When the layer height is less, that angle is greater and when the layer height is greater then that angle is less.

Since using adaptive layers causes the layer height to bounce up and down then the calculated "angle requiring support" changes.  When the layer height is uniform throughout a print, then the angle doesn't change.

 

In the image below - the cartoon on the left shows two 0.2 x 0.4 rectangles just touching at their corners.  The theoretical maximum Support Angle is 63.4°.  If an actual model has an angle above 63.4° then the extrusion on top will absolutely not be in contact with the extrusion below and you are air printing.  When the layer height is lowered to 0.1 then the theoretical maximum increases to 76.0°.

 

Now the actual question becomes "Is this the way it actually works in Cura" or is it just a "geometric/trigonometric anomaly" and my reply to that is - I have no idea.

 

Thank you
Isn't support generated above the set angle of "support Overhang Angle" even if "angle requiring support" changes?