I designed this frame last year as a gift. It holds a 10x15 cm (4x6 inch) photo.

The color change for the front file is at 4mm.

The back and the front are kept together with cylindrical 4x2 mm (0.15x0.07 inch) magnets embedded in the print. You have to insert the magnets before the last layer in the back and after the first in the front.

Be sure to orient the magnets correctly (not like me) or you will have to perform some surgery on your print.

If you have different magnets or encounter any issues with the files feel free to ask for an update or to edit the step file (but don't forget to publish a remix).