preventing all top/bottom layers

[aag 6]

This thingy https://www.thingiverse.com/thing:4256347 is supposed to deliver a flexible hygiene mask holder by avoiding to print the top/bottom layers. The STL has tops and bottoms, but the instructions say to print it without them, such that the hex infill will become visible. With Cura, however, I cannot find a way to do that. If I set Layer thickness to zero, it marks it as error. Is there a way to do that?

 

Edited August 27, 2020 by aag

[aag 6]

Never mind, I have found that Cura will still slice and print, even if the values are marked in red as erroneous!