Here's a compactible bread slicer that can be dismantled with storage for the slicer guides inside itself. You can then store it inside a cupboard standing on its side. It will fit 5 inch(127mm) wide loafs of bread.

There are two bottoms, one with holes(to save filament and time) and one without holes. The bottom without holes may be slightly sturdier, but I haven't tested it nor had any issues with the one with holes.

The 4 slice guides will lay next to each other nicely inside. The full slice guides can be stacked and may not be perfectly flush, but they should still fit fine. Personally, I only need 2-4 slices of bread at a time, and my homemade bread seems to dry out fast if I slice the whole loaf.

Print the breadslicertop.stl upside down to prevent needing supports, the guides flat on the printer bed (you will need 2 each for whichever size you choose), and the bottom as is.

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