Lithophane Bedside Light

My first attempt of a lithophane project. My niece draws fantastic photo-realistic pictures in pencil, I thought a lithophane light would show off her work really well. But as I have just been experimenting with an Arduino starter kit it just had to be motorised.
The parts were designed using FreeCad, which is a free 3d cad program. For an exploded view of the light or to edit parts, load the FCStd files into FreeCad.
The shades were created on 3dp.rocks/lithophane. Positive image. Model, Maxsize 300mm, curve 360, vectors per pixel 5. Picture size needs to be 2.83 horizontal to each 1 vertical. i.e. 2150 x 760 pixels. This will then give the correct diameter to height when set at 300mm on Maxsize. Once the STL of the shade is obtained this is scaled up in the slicer by 140%, to give 150mm high & about 143mm diameter.
The stepper motor is a 28BY J48 as in many Arduino starter kits 5V driven through a ULN2003 Darlington driver. The LEDs are 12V white strips, I mounted 18 individual s