The dreaded view range....

[still.james]

i did a search on the site and downloaded a couple of dwf's but im still cant grasp it.

i have a drawing at present that has an underlay showing and some walls show and others dont, i really cannot grasp how it actually works :(

[clog boy]

A viewrange isn't all that hard, you set the bottom of your view relative to a level, and where it is cut. Usually the bottom and the view depth are set to the same (lowest) but one can be set lower than the other (cant remember which one actually).
The Cut plane should be set above the bottom, and Top should be set above the Cut Plane.

Underlays are a different story entirely, I don't know why you only can select a level instead of a view. But usually the view linked to that level is the one you should set.

Good luck. Practice makes perfect. There's no endurance without determination, and no determination without goal.

[twiceroadsfool]

Walls that are present in the udnerlay AND in the views View range, will NOT show in the underlay.

Let me explain what this means, becasue its confusing:

If you are on the second floor, you MIGHT have a view range that reaches down below the second floor... Which means some of the walls on the first floor are included in the view range. You dont SEE them on the second floor Plan, becasue the floor conceals them, but theyre IN the view range.

If that is the case, and they are in the view range, and you underlay the first floor plan, those items will be omitted by Revit in the underlay, as it sees it as redundant information.

If you want to verify or rule out if this is your problem, turn off the underlay, and set your view to wireframe. If you can see the objects that are *missing* from the underlay, thats probably why.

I dont have it on hand, byt Autodesk has a White Paper out on this subject...