How to dimension between non-parallel objects

[Bill Gilliss]

Well, here's a way to dimension between non-parallel objects, as when you need to document diagonal clearances. As we know, Revit won't create dimensions directly between non-parallel objects, because changing the dimension in order to move one of the objects could be interpreted in an infinity of ways. But Revit will dimension between the centers of circles, so I now draw a very small annotation circle at each point I want to create the dimension between, and create the dimension snapping to the centers of the circles. Updating is fast: move one of the objects then move its circle where it needs to be. (I make mine with a 1/8" radius so they look about like an AutoCAD defpoints node, and are swallowed up in the ink of the object itself.) The dimension updates automatically. This is the simplest method I've been able to devise that is guaranteed to keep the dimension displaying the true aligned dimension between the selected points. Enjoy.

[DaveP]

Hold your mouse over the corner you want to dimension to.
Hit Tab (several times) until you see a little tiny blue dot show up.
Then click to select it.
Do the same for the other corner and you can get and "random" dimension you want.
It is pretty fussy. You need to have your mouse in just the right spot, and you'll lose it if you move before clicking.
But it is possible without any extra elements.

[Bill Gilliss]

Whoa! Much much better! Many thanks. (That is indeed one TINY blue dot.)

[patricks]

The dot shows up better if you keep the view in thick lines mode.

[MikeJarosz]

A word of advice on dimensioning non-parallel objects:

For the new Toronto LB Pearson airport, the design was a gigantic semi-circular plan. Column lines were radial from an established center point, i.e., non parallel and intersecting in one direction and concentric in the other. This created all sorts of problems with tile grids, escalators and other linear or rectangular shapes. What we eventually did was write into the specs a methodology for interpreting dimensions in a circular world. I don't have a copy anymore, but it helped a lot out in the field.