Pivot 3D object?

Jim Canale

I need help with an operation.  Imagine you have three spheres sitting in space on two or more planes.  You draw a rod from the center of sphere one to the center of sphere two.  How do you pivot the rod about the center of sphere one, so that it aligns with a line pointing from sphere one to sphere three?  I can do operations like this in 2D space with the 2D Rotate command, but I can't can't seem to accomplish this with the 3D Rotate command.   I read the help file, but still couldn't figure it out.  

Jason Bourhill

While you could do this with either of the Rotate commands, I think you will find ALIGN is much simpler approach.

Regards, Jason Bourhill CAD Concepts

Pivot-Align.gif

Roy Klein Gebbinck

Alternatively you can change the UCS.
Start the UCS command and, instead of choosing an option, click 3 points to align the UCS with the centers of the spheres.
You can then use the normal (2D) ROTATE command.

Jim Canale

@Jason Bourhill:

While you could do this with either of the Rotate commands, I think you will find ALIGN is much simpler approach.

Thanks Jason.   I had never used the ALIGN command for anything.  

Jim Canale

@Roy Klein Gebbinck:

Alternatively you can change the UCS.
Start the UCS command and, instead of choosing an option, click 3 points to align the UCS with the centers of the spheres.
You can then use the normal (2D) ROTATE command.

Right.  This works great too.   Thanks Roy!

Tom Foster

I use ALIGN constantly in 2D, rarely touch ROTATE.