Model disappear when I orbit

Back when this topic was active, there was a bug in SketchUp that could cause leader texts to fly off toward infinity when you edited the face their leader attached to. But that bug was fixed in SketchUp 2019, so if your forum profile is correct I doubt that is what you are encountering.

Distant objects are a common problem with imported dwgs. Sometimes it looks to be from working in UTM coordinates in AutoCAD, in which the origin will be at the corner of a zone and the northing and easting distances from that corner may be quite large. Other times it just seems that AutoCAD encourages people to scatter contents over absurdly large areas.

But there are other things that can also cause issues.

Can you see any part of your model? If so, since your profile says you have SU 2020, you could try dragging a selection box around the valid contents in your model and then doing Edit->Invert Selection (this command isn’t available in older versions). Look at Entity Info and see what it finds. You may be able simply to delete the distant selection to fix the model.

If you work in parallel projection, have you tried changing to perspective and then doing zoom extents? Modeling in parallel projection can lead to issues with the camera position and zoom extents in parallel will often restore a sensible camera.

@sWilliams shared the following Ruby script that can repair several kinds of issues with camera position and distant objects. To use it, copy and paste the contents of the file into the SketchUp Ruby Console and press return.

RescueMyModel v12.rb (4.4 KB)

If none of that works and you can share your model skp, members will take a look at it to diagnose the problem for you. Files smaller than about 15MB can be uploaded directly in a reply. Larger files you need to put on a file sharing site, make them public, and then share a link to the share here.