Whenever I zoom in on the model and press down on the scroll bar to change my viewpoint, the model disappears. If I focus again (by pressing f) the position of the model is different from what it was before I zoomed in.
It appears that by attempting to change my viewpoint I am moving the model.
It sounds like you might have a component that is not properly mated. It could be flying out in space at some great distance, and when you try to focus (Zoom to Fit) the view is being drawn back to include this part.
[green]"Art without engineering is dreaming; Engineering without art is calculating."[/green] Steven K. Roberts, Technomad
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Or, stop using the F key to do this. (Yeah, I know that's not a fix, but will certainly make work "possible" until finding the problem.) I think MadMango's suggestion sounds right. Is that the problem?
I use my scroll wheel to zoom and arrow keys to rotate, pan, etc. and I'm very fast with that. I also use saved and standard views. If you have a nice mouse, you can press down your scroll wheel (as a button) and rotate the model, then zoom in where you need to be with the un-pressed scroll wheel.
If its a part, you might have a sketch or something out in space. I have seen this happen often, you can edit each sketch or click on the sketches to see if anything highlights (like a point) that might be causing you your zoom issue.
We have been seeing this with tapped holes having a very large diameter phantom circle. The fix seems to be changing the size of the tapped circle to a different size and then changing it back.
It could also be a large plane or extended axis. Turn on all the options under the View menu. You may also have to Show all planes, axes, sketches, etc in the FM tree.
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