3D print does not match what's in Luban

Printing some small items on my SM Original, and what Luban shows isn’t what finally comes out of the printer.
This happened with my previous Luban version 3.14 I think it was, so I updated to 4.4 (and immediately had to go back a version, screen shot my custom settings as I couldn’t find how th transfer them, Wasted a few swear words…).

Both versions do the same thing. The models are supposed to have a rounder over area at the top of the protruding areas, as shown in the Luban screenshots, but as you can see from the photos what comes out doesn’t curve back in at the top.

I’ve re-jigged the model in Fusion 360 to create the feature a different way, but it still does the same when printing.
Never had an issue like this before, any ideas?

Luban settings (can screenshot other settings if needed)…

Did you try slicing with cura or other slicer?
You wrote about litzle prints, how tall is it?

I’ve never used Cura or any other slicer, so don’t have them set up, thought I’d see if there was anything I could do in Luban first.

I’ve done other things this size with no issue, the one without the central band is about 18mm high, 20mm across, the smaller one is 14mm high, 12mm across.

I find it weird it has no issue with the angles/chamfer on the underside, or on the bottom ring of the model, but does on top of the other rings.
All the angles/chamfers are identical and made the same way throughout the model.

Try viewing the gcode file in a different viewer (such as ncviewer) to make sure Luban sliced and displayed correctly. This would be a strange issue, but an easy one to rule out.

Also try measuring the height of the printed object to make sure the printer isn’t skipping layers. Again, this would be a weird issue but is easy to rule out

Thanks for the help, both models match the height of the designs in Fusion (+/- 0.04mm, depending where the calipers are on the printed object), so the height seems correct.

Dropping the Gcode into NCViewer.com shows all edges rounded over as per the pictures in my original post, so the Gcode looks OK.

If I get the chance in the next few days I’ll try a different slicer.

My next best guess is that the print is curling. Do you notice that the edges start to turn up and possibly collide with the nozzle at the problem points? Or does it just look like the printer is printing the model incorrectly?

It probably is curling as @bobby4718 suggests. Notice that the bottom protrusions are shaped correctly. If you watch the print while it’s running, curling shows up in areas that extend out from the main base. You can see them flex up, then push down as the print head moves over the area, then flex back up as the print head moves on and doesn’t put pressure on them.

You could try to improve the cooling by adding some external fans, or you could add supports. Cura’s tree supports would help without requiring supports everywhere. Printing it larger would also make the effect smaller and less noticeable.

I’d be very surprised if it’s curling, the models look OK apart from the top chamfer curves. The tops are flat and even (all one continuous layer), there’s no change in dimension/height. I wouldn’t expect curling to be so even across 4 different pieces (2 of each model). There doesn’t appear to be any attempt to lay down the curved inward layers, I’d expect to see something on top of the curled up layers.
Something to think about and explore though. I’ll see what effect printing at other settings has.

It’s just weird, nothing I’ve printed before has had this issue, usually it’s obvious curl at some point, or lifting, but not so evenly.

I guess I can still use the models (tokens for a board game), I’m just hoping to find out what caused it in case it happens again and I do need to correct it.