Hood for Mamiya C220/C330 80mm TLR Lens

prusaprinters

This is a lens hood designed to fit the 80mm lens for the Mamiya C220 and C330 family of twin-lens-reflex cameras.The dimensions are roughly worked out from online images of the original metal hood.The diameter of the clamping section is very close to the outer diameter of the lens, and the thumbscrew provides a clamping force on a flexible tab that secures the hood in place.The clamping ring is 1.5mm thick, so that it can fit the narrow gap between the taking and viewing lenses.I placed the part on the build plate with the clamping ring at the bottom and turned on supports. When it finished printing, it was surprisingly easy to twist and wiggle the part enough that all of the supports let go and it came out with just a few strings hanging on.The inside surface is a bit on the shiny side for a lens hood, so I lined it with a long strip of gaffer's tape. Friction tape is pretty much the same stuff and ought to do the job nicely.If you are into painting your parts, this lens hood would be well served by a coat of flat black on the interior surface.I used what I had laying around for the thumbscrew: an aluminum M4 thumbscrew, like used to secure computer cabinets, and an M4 brass insert. Use whatever you have!I have provided the original FreeCAD model so that you can tweak it if needed. There is a spreadsheet in the model that defines many useful constants that can be twiddled. I made a dog's breakfast of the units, mixing fractional and decimal imperial units with millimeters…kindly overlook that and type whatever unit abbreviation you wish to use in the spreadsheet and it will do the conversions for you.