This soap dish is inspired by modern bathtub designs I have seen. There is a slight slope to the insert where the soap sits such that it is supposed to drain into the base though the hole in the middle but the slope turns out as a terraced effect when printed that I wasn't expecting but that looks kind of cool at the same time.

Made in Blender. Printed on a RigidBot using PLA at 0.2mm layer height, 0.8mm shell, 10% fill, 195C print head temp, 55C bed temp, no supports. I printed using Cura as the slicer, and it took around 3.5 hours at the default scale.

I've only tried to print this on one type of PLA extrusion printer so your experience may vary. I've included the Blender file in case anyone would like to make changes/improvements/derivatives, etc. Have fun.

Depending on your soap size, you may need to scale this up. This was designed to be a snug fit for Dove soap as that is what I use most, but it should scale well.