Here's an example screencap video - here I run the View > CPlane command, and snap a point onto the face, then right click to accept the default rotation around that surface normal.

Then I use a right click on View > CPlane to reset it, and then place it again this time dragging the x axis line during the 2nd step (that says "Adjust axis orientation") to make horizontal x axis line of the view to go through a specific point:



- Michael

Or also another way you could do it is to transform the object so that particular face is flat in one of the regular top/front/right views.

You can do that using the Transform > Orient command, which uses the orientation picker similar to setting a cplane, except with Transform > Orient you use it twice, one to set up the base orientation frame and then to set the target orientation.

- Michael

Hi Beefy,
You can use the script below "CplanAux.js", this is how it works: A = CPlane on a selected FACE / A = Return to the original Plane.

Thank you very much everyone.

I've been pulling my hair out over this today, and thanks to your help I now realise what I was doing wrong.

I only had the 3D viewport open when I was using the Cplane tool, and as a result I did not see any change when using the tool.

With all viewports open I immediately seen the object rotate and the face become normal to the view. Exported the applicable faces and imported into another program, and checked dimensions. Everything perfect.

I'm a very happy camper,

Keith