Maybe you know some way to optimazation your model before 3d pdf file making?
Turn off any layers for things that you can't see.
U3D files really don't work with large files - even with small files they are very slow.
Is there any reason you have to have the 3D model in a PDF?
You can save a BIMx file that will give a much better result.
The end user doesn't even need to download a viewer for thier desktop or APP on their mobile device (although these are better), as there is a WEB viewer available in the BIMx Model Transfer site (link is in useful links above).
One of the forum moderators.
Versions 6.5 to 25
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