Cannot determine board outline

Hi experts,
I am having getting an error message in KiCad Pcbnew 3D View:
"Unable to find segment with endpoint of (xx.aa,
Cannot determine board outline"

In order to avoid any gap issues between edge cut lines and/or corners, I didn’t draw the edge cuts free-hand by dragging the mouse cursor across the screen, instead I entered the X and Y coordinates for each four edge cut sides using the KiCad “Line segment properties” window separately as shown in the image below.


Since the error persisted, I redrew the edge cuts a few times even by varying the X/Y coordinates slightly (variation in 1 - 3 mm rage). Unfortunately the problem remains,
The strange point is that the error corordinates reported are different each time. The last error message I got shows the X/Y corordinates even outside the PCB area.

Where have I made a mistake?

For your reference I have attached the kiCad version, PCB and Cache files herewith.
Thanks for your advice in advance.
Best regards
KiCad Version Info.docx (12.2 KB) 200914 scratch_circuits_test.kicad_pcb-bak (453.0 KB) 200914 scratch_circuits_test-cache.lib (13.8 KB)

The easiest way to draw a PCB outline on Edge.Cuts is to use a coarse grid.
A grid of 1mm usually works well.

When you zoom in on the corners of the PCB on Edge.Cuts, it’s also easy to select them and drag the endpoints by the little squares that show up when a line segment is selected.

I had some trouble downloading your PCB, had to remove the last “-” from the link. Looking at your PCB now…
Hang on.

[Edit 2:]
A link that works to your pcb-bak file is:
(I removed the dash).

I also had a quick look at your board outline, and it uses these coordinates:
55, 40
184, 40
184, 96
55, 96

Endpoints seem to match nicely, but still the 3D viewer complains, which is weird. I don’t know the cause of it (yet). But first dinner time. Maybe I’ll be back in an hour or so.

The 3D viewer pointed out the bad line segment with Dim’s of:
177.975, 78.35 [mm]

If you set the cursor to the bottom-left corner of the PCB edge cuts, hit the SpaceBar (to reset Zero ref) and mouse over to around 178,79, and zoom-in, you’ll see the problem… (bottom of the PCB panel shows Info).
There are More to find and delete/resolve… Use the 3D viewer to help identify the locations

Screenshot shows it… (look at the cross-hairs and see the Red line)

The Second one (at 201,56 [mm]]

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Yep, a wild and unconnected line segment.

There is another one at coordinates: (201.7, 56.7)

If you delete both lines then the board views fine in the 3D viewer.

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Hallo paulvdh and BlackCoffee,
Thanks a lot to both of you for your meticulous detective work in tracking down those “wild” segments.
I reproduced the solution applied by you and it worked at once. The 3D view is now as it should be. No more error messages. Wow!

Before reporting the problem in the forum, I had myself tried enlarged all corners and scanned along the edge cuts as well but didn’t find anything despite repeated attempts. Now I understand the reason, I was looking to close to the edge cuts. I should be more open minded in future and search more generously.

Thanks a lot to both of you for investing your valuable time in helping me.
This is a big help and a valuable lesson for me.
Best regards

my advice is make use of FreeCAD’s KiCad StepUp plugin.
I typically draw a really crude board outline in KiCad then load the pcb file into freecad and properly constrain the pcb outline exactly where I want it before pushing the outline back to KiCad

The biggest “detecive work” I did for this post was to figure out how to download your PCB file.
Tried adding the “bak”, did not work, some other tries, finally just removed the dash.

For the PCB I right clicked on the “Layers manager” in Pcbnew and turned off all layers, then turned on just the “Edge.Cuts” layer, and the problem is quite obvious in that way.

I don’t see why drawing the bounding rectangle with the mouse should be a problem if you do it in one pass using the polygon, er, line tool and a coarse grid. After you have closed the rectangle you can test it right away. Rounded corners can be added later.

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