Model disappears when you rotate around it?

Suddenly, when I pan around my model in edit mode, it vanishes. Then I can’t make anything show, even if I leave edit mode. All the other objects are fine. But one object, if I go into edit mode and move my view, the object vanishes and so does everything else including the background grid, and if I go back to object mode, everything is still invisible until I reload the file.

Bug or some weird setting I don’t know about?

Attachments

Bike Saddle.blend (1.75 MB)tilted arc.blend (415 KB)

Check scene size is not too large or too small
Check viewport clip start/end distances

Please ALWAYS supply your blend file for ALL support questions so we don’t have to rely on pure guesswork !!

you can use this to upload your blend
http://www.pasteall.org/blend/

I uploaded it to that pasteall site, can you not see it through the forum here? Look at the tilted arc.blend file.

I downloaded and opened this blend and it completely froze my computer.

wow. okay. Sorry.

Was this blend created on a mac? I’ve had that problem before.

yes, I work with Blender for a living and I’ve never had that happen.

I appended the scene and I think your problem is scale and clipping. Your bike seat is more like a jumbo jet, it’s 300 meters long. Standard clipping (the point at which blender does not display an object) is 100 m. You should probably scale everything way down, or you can increase the camera clipping value.

I prefer to think in millimeters. What’s the difference from Blender’s perspective if I’m not rendering and image? Do I need to change the units?

If you are simply using it for geometry, or for printing, it’s not a big deal. By default the blender camera cannot see parts of an object more than 100 meters away, this can be increased (end clipping). I guess for printing the biggest issue is that you may have a skewed idea of what the object will look like. By default viewport and camera use 35 mm focal length. This give a much more highly distorted perspective and parts of teh object closer to the view will appear much larger. Basically modeling to scale, and using a higher focal length (50-70) will give a better idea of the true shape.


Here is the clipping value at 100, and most of the object is not visible.


I see. Thanks. And yes, I design for 3D printing, so it shouldn’t matter too much.
I tried adjusting the clipping, and making everything a tenth as big, but it still crashes every time I look at that one object. Probably safest just to trash the whole file.
Thanks very much for the help.