Alcatraz Puzzle

This is the Alcatraz escape puzzle and and solving it is quite a challenge.
Insert a 9 mm ball bearing in the large hole and find your way to the small hole. You can decide to use the solution.png as your guide or go cold turkey by not using it. Looking through the windows helps a lot.
If you want to see the solution in a 3D model then load the file solution.scad into OpenSCAD (https://www.openscad.org/downloads.html) Also get the files Chamfer.scad and core.scad into the same directory.
3D printing may be a challenge for your printer. Make sure you disable all support generation otherwise the tunnels in the puzzle will get filled and render your puzzle useless. I found that after printing I had to sweep the tunnels with a screw driver to clear some stringing that happened.
The model was generated using a Java program that generated OpenSCAD code.