The Compak K3 espresso grinder has two metal pegs where other grinders have a portafilter holder. I made my own to be able to leave the grinder going not having to balance half a kilo worth of brass for the 20s it takes for a double shot grind.
The hardest design issue was fitting the holes around the not entirely parallel pegs in a way that gives a snug fit while being strong enough to support the portafilter handle weight on the hook at sufficient distance to clear the spouts on the underside of the handle. First three designs were too flimsy and broke.
M3D micro with what I had left of their original pearl white PLA. 0.25mm layer height, 25% infill and only two spots of supports needed.
