Unexpected rotation of viewpoint

The file is uploaded to illustrate the problem. On the timeline, between 51 and 99, there is a slow rotation of the four screws. This is supposed to happen. But at the same time, for no reason I can identify, there is a slow rotation of the entire object, or perhaps the point of view. It is not clear to me what is instructing the program to execute this unexpected rotation. Where should I look for this unexpected instruction?

Thank you for your insights. Michael VS 8-11-2018 expts.3dm (1.4 MB)

Solved it. I went back to an earlier save in which the problem had not yet appeared, and rebuilt the model from there.

I don’t understand how the problem arose, but I managed to work around it. Michael


I opened your model and could NOT see any rotation of the entire project or view.

Sometimes a model can get slightly corrupted during the drafting of the animation. Saving and reopening the model often cures such minor inaccuracies. Whenever an model shows inexplicable behavior I try this trick before anything else.


Thank you for your suggestion, Luc. I will use it. Regards, Michael