A GUI for generating STL files based on the gerbers for outline and masktop or maskbottom. You can also use this tool to create a solder stencil. It’s primarily designed for prototyping THT PCBs. The solder-stencil part is primarily for SMD PCBs
I had a need to test sizes of custom components, as well as PCB Layout in general (Eg, I’m making a project with a rotary dial, and needed to check spacing with the knob attached to my rotary encoder as I’m trying to make the pcb as small as possible, as well as needing to check mounting of the custom encoder part too)
Obviously 3D Printing via FDM will have different tolerances depending on your printer. For my testing, I was printing on a resin printer which is far more accurate.