Movie Film Spiral Developing Tank

thingiverse

This is a movie film developing tank, similar to the old Lomo tanks. Exposed film is wound onto the spiral and placed in the light-proof tank while in darkness. Developing fluids are poured in through the central hole in the tank lid and out through the spout on the side. The tank includes a pouring spout and clamps to hold the lid on. The lid is secured to the tank with sliding tabs, and a vent allows smooth pouring. Two film sizes (8 and 16mm) can be used in the same tank by swapping the central hub piece. The spiral platter, hub, and top retaining ring are secured together with a bolt piece that also serves to block light from entering the central hole, and provides a handle to rotate the spiral for agitation while developing. Files for 50-foot and 100-foot (15 and 30m) film lengths are included. The 30m tank and spiral just fit on my 300x300mm build plate, and the 15m size should just fit on a 220x220 plate. Support structures are included on all pieces, you shouldn't need to add support in your slicer software. Update: By request I added a 35mm hub, bolt, and taller tanks to fit 35mm film. I haven't tested these, let me know if you try them out! Second Update: Added clockwise and counter-clockwise spirals in case anyone finds that one direction works better than the other. I try to load the film with sprocket holes down and the film winding onto the spiral in the same direction as the film's curl. The new spirals also have an additional (non-removable) thin support ring around the outside to aid in printing. The spiral inner-hub-support should also now be more easily removable after printing. Don't forget to remove the small support piece in the notch between the hub and the inner spiral, the lower film edge should be able to pass through it. Also added a reel caddy and bar to aid in loading the spiral. The caddy holds a 100' spool of 16mm film. The tip of the hub bolt is placed into the inset circle on the bar. This allows the spiral to spin in place while loading film from the spool on the caddy. Third Update: Added a 9m (29 feet) spiral and tank (untested). Should fit on 180x180 build plate.