Distagon f/4 40 mm C lens hood

I recently purchased a Hasselblad 40mm C f/4. I love medium format cameras and lenses. The are sharp, work very well, and are built to last, this lens is no exception.It's a beast weighing in at 1.375kg ~3lbs. I've been scared to shoot it because I didn't have a filter to mount on it. Older series Hasselblad lenses (and some Rolleis) take bayonet style filters and lens hoods. They work great but are hard to come by, and expensive if you do find them.

My idea was to design a lens hood that