I was wondering if anyone here has ever had the diameter dimensions on a 2D drawing suddenly, spontaneously change. A couple weeks ago, I created a drawing with some 2D views in model space. I find it a lot easier to dimension parts in model space, than on a layout view.) Anyway, I actually built parts from the 2D views. Then today I re-opened the drawing and found that all my diameter dimensions were changed. There is no problem with linear and ordinate dimensions - just diameter dimensions. For instance, a diameter dimension of .1285 changed to .66258. I can't imagine how this would happen. I can place new diameter dimensions, and they are correct. But why did all the old dimensions change?