This is my attempt at a #gridfinity pencil sharpener that collects the shavings. The entire thing is 1x1x6u, the shavings box being a 5u gridfinity box itself. I used a sharpener bought from HEMA, but I am not sure if it is a "standard" one. It's about 9.5 x 14 x 25mm. The lid needs to be printed upside down and does require support. You can support-block the 2 small overhangs at the top, they bridged just fine for me. To install the sharpener, remove the blade-screw, put it in and put the screw back. If the snap fit is too tight, sand back the locking parts a hint.