Objects drawn at z=0 won't stay at z=0

My drawings consist of 2D & 3D and at times can become rather very large files. I have a problem with Z axis. Lines & 3D objects seem to move around at will. I use “project” as needed to try to help this problem—and—that seems to work when I am actually drawing a line; however, when I go to do a random check I will fine objects on on Z as they should be. I keep all 3D objects on different layers—so— I can turn them off and “SetPt”. This actually turns out to be a suggestion rather than a command. And, I will find objects on Z in front view and off Z in side view—back and forth. Trying to correct this problem can be a task because “Vertical” as a “Move” option doesn’t seem to work—nothing happens at all. I have to measure the distance —and enter it to get the correct move in the Z axis. I have thought that it might be the Video card; however, I only get errors in the Z axis.

Is anyone having this problem? Any suggestions?

If you are seeing an object on CPlane 0z in one viewport, but off of it in another, then those two viewports are using different CPlanes. As for why the CPlane is changing, Is it possible you are using namedViews, which can change the CPlane when restored?

I might suggest opening Options -> Modeling Aids, and switch from Standard to Universal construction planes. Then set the CPlane in one of your viewports and all the others should update to match the one you just set. Let us know if this resolves the other problems you are seeing.


Sam—I am not using any C Planes. All is World. No Names Views. I changed to Universal—just for the hack of it; although, both setting have to do with “Construction Planes”—which I never use.

As far as resolving problems----I don’t have much hope. This has been an ongoing problem for as long as I have used Rhino—that’s been around the start of v4.

Thanks for your time…………………………

Do you have a file that demonstrates this, with the object zeroed on Z in one viewport and not the other? It would be helpful to take a look. Your are not accidentally dragging these guys are you? My other suggestion would be in Options -> Mouse make sure Drag selected objects only is checked and set the object drag threshold extremely high (999 is the highest it will go)

I can assure you though that the Z wandering you are seeing is not something that is indicative of Rhino (I have actually never seen it), so you should have hope, we just need to find the problem.

Not right now on the file I’m working on. I’ve corrected everything; however, it is a reoccurring problem—and I’m sure it will come again—unless you have scarred it off–(that would be nice). I’ll post it if it happens again. Actually, I probably have that—if I can get time to post all files. Long story why I do this; but, I do a save as every time I work on a file—just change the date–which is part of the file name—So…. I may end up with 20 or more files that are in progressive stages of development. I’ll try to send them along to you at your steve@mcneel.com address.

Thanks for your time……………………….Joe

Shot in the dark…Could History be a culprit here? Check and see if History is on. If so, try a test of turning it off to see if this unusual movement stops.

Best regards,

This happens to me, but it actually happens in any CAD or Drafting application where I heavily use modeling aids and object snaps. Using the Project Modeling Aid (_ProjectOSnap command or checking the Project checkbox in modeling aids) is my solution for ensuring that what I am drawing stays on 0z of the view in which I am drawing. But I think you are already doing this. For me, if I ensure that the Project Modeling Aid is on when I am drawing or modifying my objects, I never get unexpected results.