The original Tantillus does not have Home sensor for X and Y, http://www.tantillus.org. For me this is very important because my idea of a 3D printer is just "click and print".So I made this addon for the acrilic version (which I bought from http://www.indiegogo.com/tantillus) which requires no modification to the original parts.These parts are easy to print. Insert the nut and the M3 screw, fix the micro-switch with the Self Tapping screws and conect to the driver board.The Y Home Sensor is fixed on the top of the structure on the left side, close to the top-right-front corner. The X sensor is fixed on the front panel, through the front window, close to the top-left-front corner.For calibration, it is recomended to first move the cariage manualy to the extreme position and then adjust the sensor (you can hear it click). This will prevent that it breaks in case of an excessive cariage movement.BOM vitamins needed: 1) 2x micro-switch 20mm like this one: http://br.mouser.com/ProductDetail/Honeywell/ZV10B70A01/?qs=sGAEpiMZZMtFyPk3yBMYYI0nvXV6ddkcmIv%2fkeci2vU%3d 2) 4x self-tapping screw 2.2x9.5mm like this one: http://www.conrad-uk.com/ce/en/product/228737/TOOLCRAFT-DIN-7971-flat-top-sheet-metal-screws-with-slot-Galvanised-steel-22-mm-20-Units/2304030&ref=list 3) 2x screw M3x4 4) 2x nut M3