How to Select workplane

[mmiles]

Ok, I am modeling a window unit (for all intents and purposes, I am playing with boxes) which is based on a 2D block that I drew in elevation.

Block inserted into 3D environment (default ACAD 3D template) and 3D rotated it (up) as if it were standing on a floor. Using the model box icon on the Ribbon, I am making the different parts of the window unit. I want to know if there is a way to select what face, or axis, I want to draw the box. As it is I am selecting a corner (intersection of lines) and attempting to select the opposite intersection, but the program is selecting a work plane on it's own, and I want to know how to control that behavior.

thanks.

[Jmurphy]

Look at this help topic: About Controlling the User Coordinate System (UCS)
http://help.autodesk.com/cloudhelp/2016/ENU/AutoCAD-Core/files/GUID-8272C86D-219F-4673-8640-E87CB06F4C59.htm

[mmiles]

Thanks Murph, I will look at that. I'm still learning to navigate contemporary "help"...

It seems that ACAD also has an intuitive aspect to it - while drawing (i.e. rectangle) the cursors sometimes snaps and reorients itself to a different axis. I don't know how, or why, but, I was hoping to find a way to toggle axis' while picking points. Live action work plane selection, or something. Any tips, anyone?

thanks, again.

[jaberwok]

In the meantime, you might want to turn off Dynamic UCS (F6).