How to avoid creating hidden lines from intersecting shapes

[colin]

I couldn’t get your example model to show any stress lines, but still you could try the extension that sWilliams made, here:

How to make a selected face be truly flat

Colin, I’ve needed this function in the last week or so and decided to make a first try at writing a solution. The code is based around Eneroth’s flatten to plane, a bit of clean up code from Dan Rathbun, with maths from Emil Ernerfeldt. Fitting a plane to many points in 3D Usage: Select any set of faces and edges Click on the Extensions menu > Flatten to Calculated Plane The selected geometry will be collapsed onto a plane that represents a ‘best fit’ to the selected entities. Any edges i…

The file you download is sw_flatten_to_calculated_plane.rbz. Install that, then select a set of faces and edges that are supposed to be coplanar, but might not be, then choose the extension in the Extensions menu. It may prevent stress lines from occurring, or get rid of them if they are already there.