Hi Angelo, also one other note - if you have a series of planes and you want to compress them back into a single plane, you can do that by using the "flat" snap with the edit frame scaling grip from a side view like this:








Also if your planes are angled so you can't easily get to a side view you can also use Transform / Scale / Scale1D which will allow you to pick 2 points to define the flattening direction, then type in a scale factor of 0 to flatten in that direction.

- Michael