Split Reel and core adapter for movie film, 16mm, 35mm & 8mm

September 2025 - V2.2 - added a boolean flag to the VarSet in the FreeCAD model to allow for winder spindles that have a square section throughout.

V2.1 - made the core thickness parametric to cater for 35mm and 8mm film cores. Uploaded .STEP files of base sides for 8mm and 35mm film. Diameter is for 400ft (120m) film. VarSet in the FreeCAD file allows adjustment of both diameter of the reel and width of the film.

V2 - Remade my design in FreeCAD 1.0.2 and made the reel diameter parametric with a VarSet variable. Also made .STEP files of 200mm diameter and 251mm (9.9") diameter reels. Printed the 200mm version in PLA on a Prusa Core One. The FreeCAD design file is also uploaded.

This was created in FreeCAD to allow spooling of unexposed 16mm movie film from 400ft cores onto 100ft daylight reels (in the darkroom) - and for spooling developed film back onto the cores for long term storage.

The film core fits onto the keyed centre, so it doesn't rotate - the other side of the reel is screwed on, and held in place by the optional locknut. The nut prevents the reel from unscrewing while film is being wound. Fits onto a 16mm hand winder. Once wound, the film and core can be lifted off the reel.

The film core is held away from the edges of the reel so the film doesn't rub.

Mine are printed PLA - at 0.2mm layer height. Pretty much default settings should be OK.