I was just admiring the calendars on the CDO site and of course, admiration leads to emulation. Being a cube, this is just a six month calendar, but when July comes, you can open it up, reverse all the folds and there are the next six, ready to go. June and December aren’t the easiest to read, I grant you, but folding accuracy on this scale is problematic.
The type here is Igino Marini‘s wonderful IM Fell Double Pica PRO, which dwells in this world under an SIL Open Font License.
Crease pattern here (the curiously versatile jasmine tea cube) and a PDF of the calendar here — print the latter back-to-back. (Schiena contro schiena, forse).
While I’m here, let me also point you at a nice video, posted by Leyla Torres, which provides a slower, more in-depth view of how to collapse the Smart Waterbomb.
