Slide into the filament reel so that filaments from different suppliers all fit into a standard 15mm diameter bar/tube/rod (e.g. copper tubing). Currently I've got support for four kinds of filaments: - makerbotfilament (the original makerbot filament) reel-diameter: 52.5 mm reel-depth: 55 mm + 0.5 mm screw-diameter: 30 mm rod-diameter: 15 mm + 1 mm - villageplasticfilament (Similar to makerbot filament) reel-diameter: 51 mm reel-depth: 55 mm + 0.5 mm screw-diameter: 30 mm rod-diameter: 15 mm + 1 mm - cheapfilament reel-diameter: 31 mm reel-depth: 87 mm + 0.5 mm screw-diameter: 26 mm rod-diameter:15 mm + 1 mm - chinafilament reel-diameter: 38 mm reel-depth: 76 mm + 0.5 mm screw-diameter: 26 mm rod-diameter:15 mm + 1 mm The Autodesk Inventor (IPT) files are also included in three files: Adapter.iam (assembly), Screw.ipt, Bolt.ipt. Both the screw.ipt and bolt.ipt files have a design table containing the different variations of the part - you can modify dimensions as you need for other applications and other manufacturers and alternatively sized rods