SummaryRotate about the central axle to transform between a heart and an ellipse. My first print-in-place "mechanism". Think twice before printing this for Valentine's Day, unless you're sure she's as geeky as you. ;)Print SettingsPrinter Brand: PrintrbotPrinter: Simple BlackRafts: NoSupports: NoResolution: 0.2Infill: 15% is fineNotes: Thick walls to ensure axle is solid.... 4 shells, 4 solid layers.Post-PrintingThe axle should break away from one or the other half with a gentle twist of the two halves. There's no need to break it away from the other half, unless you're OCD. If necessary, separate the parts by sliding a knife down between the two body halves, and at either end of the axle. Don't cut deeply at the axle, in case you weaken or break it.How I Designed ThisBased on a design I found on the Internet (e.g. http://www.cutoutfoldup.com/1609-ellipse-to-heart) My design is available at OnShape.com... search Public projects for "Ellipse-Heart". The variable "tol" can be used to adjust the tolerance between the parts, in case you want to try printing a more accurate (or easier to separate) version. Mine is set at 1mm. You can also adjust the thickness of the model. Mine is set to 10mm which results in a 3mm axle if the tolerance is 1mm.