Loft/Sweep - ERROR - Swept Body has Self-Intersection

When trying a Sweep - or a - Loft :: you can get an error - swept body has self intersection with at least one point

Somebody else has had this problem and posted something; but there's NO answer yet. *What causes this error?*  If there is a line I am trying to sweep along, what are the rules for how the line has to be drawn, relative to the body being swept, or the bodies being lofted?

Can I take a curved/spline that starts out tangent or runs kind of parallel to the shape I am sweeping? …or does the line have to be solidly perpendicular to the shape being swept?

P L E A S E - help us better understand what the constraints of the tool

Thanks in Advance!!

Hi @VmusicV!

The self-intersection error appears when the sweep path has a smaller radius somewhere than half of the width of the swept cross-section. In this case, a solid body could not be maintained after applying the tool, it would end up in something like this where the open curve was the swept path, the closed one is the cross-section:

Shapr3D is a solid body modeling software, it is not allowed for any tool to split the bodies up to surfaces.
The problem with the loft is technically identical, but there is no exact sweep path to follow. If the cross-sections following each other do not have enough space between them, the loft will also end up in self-intersecting geometry.

There is no strict rule to tell you what will these tools make fail, but tweaking the guides and cross-sections will always help a bit :slight_smile:

If you could upload the workspace or a screenshot, I am happy to take a look at it.


Thank you!!! REALLY Thank you so much. This is very helpful.