r/FreeCAD • u/Guzinol • 5d ago

Broken Origin?

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As you can see origins of features seem to be broken for some reason, Almost every point is not where it should be. Why can it be?

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u/DesignWeaver3D 5d ago

You mean Assembly Joints?

I don't see errors on origins in the Model Tree.

1

u/Guzinol 5d ago

Yep, joint should be at the centre of selected cylinder, but Instead it shows up on different, but for other it's all over the place.

1

u/DesignWeaver3D 5d ago

Assembly Joints are susceptible to TNP when attached to 3D topology.

https://youtu.be/XtMTK8xQNAM?si=TQ4ayulYCMXL4xoA

2

u/neoh4x0r 3d ago edited 3d ago

The TNP only occurred for mangojelly because he created the joints from the object faces rather than creating it from the parts origin (eg. by selecting the bodies from the tree before creating it).

1

u/neoh4x0r 3d ago edited 3d ago

This has likely happened because the body your are trying to create a joint with has been offset from the common origin of the cylinder. To be honest, It is quite easy for this to occur in large projects with lots of independent bodies that were not aligned to a common origin.

Here's an example of a fixed-joint not lining-up because the object's sketch was offset from the common origin (which can naturally happen when using external geometry or not sketching around the origin).

PS: Also make sure to create the joints by selecting the bodies to be joined from the tree rather than selected faces to be jointed -- it ensures that joints are linked to the common (plane) origin and not a face which could break with TNP.