I wanted to be able to use my cokin filters with my nimslo 3d camera so i designed this in onshape. 

Added a cutout so you can still fit an arca swiss plate, and a 75mm filter version. 

I printed with supports on above the arca cut out area. 

Tolerances are a little tight and I printed in pla, so if you're using abs/asa or other filaments with shrink you may want to compensate.