# Alternating number of lines for the shell between layers

Is is possible to have alternating numbers of lines for the outer wall between each layer? So, say, one layer will have 3 lines for the wall, the next layer, 2, then the next layer 3, then 2 again, and so on? Even better, if I could group them in twos: two layers with 3 lines, two layers with 2 lines, repeat until done.

I use Cura, but if other slicers can do this I'd like to hear about it, too.

It is possible to get an alternate extra wall in Ultimaker Cura, the option is called Alternate extra wall. It can be used to catch the infill more firmly, strengthening the print.
• I find the claim of "catching" infill between the extra walls somewhat dubious unless you also enable zig_zaggify_infill ("Connect Infill Lines"), which is a really good idea anyway because it vastly reduces travel moves and the associated problems with material loss due to oozing while "combing". With this option on, infill doesn't just start/end at points sandwiched between the extra walls, but has whole dashed segments for roughly half the total perimeter pressed between them. – R.. GitHub STOP HELPING ICE Apr 10 at 22:51