Plumb Cut in 3D Family

[RPU_eric]

Hello all. I am fairly new to 3D family creation and am having some problems getting this to work! I am trying to create a void within the OOTB W-Wide Flange beam family (or any beam family for that matter) so that I can apply a plumb cut to the start or end. The problem I am having is when I try and apply a parameter for the angle of the plumb cut. I have created the void without a problem, it is simply the constraints which are giving me problems. I've attached images of what I have been trying. When I apply the parameter to the angular dimension I get error warnings that the constraints cannot be satisfied. I've aligned and locked the vertical and horizontal legs of the void extrusion to the appropriate reference planes such that the void flexes properly with the family. However, it seems that Revit is trying to rotate the reference plane to meet the angular parameter rather than rotating the angled leg of the void extrusion. This seems to occur whether I place the angular constraint in the "Extrusion Editor" or outside the editor in the family itself.

What am I missing here? Your input is appreciated!

[dmahan]

try this, add vert reference plane out in space past the end of your beam at some distance, label this plane offset cut, add dimension parameter from this plane to end of beam.
now create the void extrusion for cut with back on this plane, lock bottom to beam depth, add cut angle, the while in extrusion editor add parameter for angle of cut.
close the extrusion editor. do the cut geometry. now you can move the extrusion cut by changing the offset distance to zero, this should cut the end of your beam.
This will also allow your to move the cut back and the beam will be square cut. It does not work if you try to change a void angle to zero. we are just move the cut away from end of beam. another thing go ahead and make another new void cut, to work at angle in the other direction. rename the two cut void angles one for positive angle and other for negative angle, this will allow you to pick one parameter for beams that are sloping up or down.

Hope this helps