How to measure flatness deviation without CAD in ZEISS INSPECT?

[[Su...]]

Hi everyone,

I'm working with ZEISS INSPECT and currently only have scan data (STL mesh) — no CAD model is available.

I would like to measure the flatness deviation of a planar surface, and ideally obtain the maximum and minimum deviation values from a defined reference plane.

Is there a way to:
1. Create a reference plane directly from the mesh?
2. Compare a selected surface region to that reference plane?
3. Generate deviation values (min/max/avg) or a color map without needing a CAD?

Any help, screenshots, or workflow steps would be greatly appreciated!

Thanks in advance.

[[Na...]]

Hi,

you can construct elements directly on a mesh. For GD&T you can use the quick creation tool. Selections are done automatically by the software when using fitting elements and you can of course select manually (https://techguide.zeiss.com/en/zeiss-inspect-2025/article/general_selections_in_3D_view.html).

 

 

[[Sw...]]

Hi

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I did try to follow the same steps but was unable to represent the deviation. I am using a .stl file. The aim as mentioned was to check the surface flatness, of a  planar sheet. The problem is that right after I click the flatness, it doesn't represent me anything when I click on the surface.

 

Edited April 23
It has been resolved

[[Na...]]

Hi,

maybe the mesh is not automatically recognized as a plane feature. You can either create a fitting plane directly on the mesh or select first with "select on mesh" for example, and create a fitting plane from the manual selection. The resulting plane can be checekd for flatness:

 

 

 

 

[[Sw...]]

Hi

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Thanks for the guidance. I have attached some images where I am unable to view the flatness deviation in some of the regions especially the curved regions of the mesh. How can I view the deviation on those grey regions marked with black arrows(as represented in the image_1b)?

Also, 0.4 was the tolerance that I had set. What does 4.5(actual) in indicate(as seen in the image)?

________________________

For Reference

Image_1a = 2D orthographic view

Image_1b = Isometric view

Image_1c = Isometric view of scanned mesh .stl (curved at the end)

 

[[Na...]]

Hi,

please click on Plane 2 in the explorer -> RMB -> Edit creation parameters and use the selection tools on the bottom of the 3D view to select the missing areas. Then press OK and the flatness will be calculated with the new selection.

Please see the techguide for a detailed explanation: https://techguide.zeiss.com/en/zeiss-inspect-2025/article/cmd_inspection_check_flatness.html

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Nanno

[[Sw...]]

Hi

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I did implement the way you instructued. It definitely works but the catch with my scanned .stl file is, I have to click multiple time at different regions as is shown in the image in the arrow which points to the multiple clicks that I did on to the mesh file. Is there any way to select the entire region easily(as you can see there are still so many regions left)?

 

[[Na...]]

Hi, 

you can "select all" with this button in the state of the screenshot:

[[Sw...]]

Hi

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Thank you so much for the help. So, I had couple of questions to which I need your expertise and guidance. As you can see in the images that had been sent before, we have a planar membrane that we scanned, now in order to measure the surface deviation or the surface rms of the scanned file, I see 2 methods i.e.,

1. Check Flatness Feature vs
2. Creating a CAD model for the same and then aligning with the mesh file, following with surface comparison feature

I want to understand, amongst the above that I mentioned which would be the most optimal method to go for since our application requires to achieve rms of 1.5mm that we are doing with the mechanical assembly but to verify, using Inspect 3D, what would you recommend us?

 

Let me know your thoughts.