Dwarven Dice Mill – Crank Dice Roller: a Copper Wheel Lifts Your Die Up a Spiral Rail and Drops It Down the Tower

Über dieses Modell

Turn the crank of this dwarven forge and it rolls your die for you. A three-armed copper wheel scoops the die out of the hearth, pushes it up a brass spiral rail and over the top. At the top the rail runs out past the wheel's arms, so the die is let go every time. It slides down the chute, drops through the watchtower onto the lower ramp and tumbles back into the hearth, where you read the result. You never touch the die, and the next turn picks it up again. It's a tabletop / D&D dice roller with a real mechanism you can watch. The die runs in a window slot framed by dwarven runes, and arrow slits in the tower show it tumbling down. A carved dwarf-king medallion guards the tower. HOW IT WORKS • The crank turns a 3-arm rotor directly (no gears to jam). Each arm sweeps through the hearth trough and pushes the die up along the shroud. • At 9 o'clock the die rolls inward onto a fixed brass rail (two ledges, one on each side of the rotor). The rail spirals outward, then runs in a circle 7 mm inside the arm tips over the top. The arm pushes the die until it slides off by itself onto the 30° chute. If it stalls, the arm keeps pushing it, so it never hangs at the top. • The die slides down the chute (R1) and falls about 35 mm onto the 24° lower ramp. It tumbles down into the hearth trough, the next arm picks it up, and so on. • In steady use it's about one roll per crank turn. The die waits in the hearth for the next arm. DESIGNED AND SIMULATED (not yet test-printed) • Die path simulated in the wheel plane every 0.5° of crank rotation: the arms push the die and gravity settles it, for 16, 20 and 24 mm dice plus a 23 mm d20 envelope. Every run gives a lift, a release and a return to the hearth, with 0 jams over 2.5 turns from 3 start phases. • Trough-mouth test: a die dropped onto the lower ramp at 155 positions and rotor phases always ends up in the trough or lifted. 0 pinches. • Tower clearance: 34.8 mm between the lower ramp and the chute above it, and a tumbling 24 mm d6 (17 mm half-diagonal) passes the whole path. • Rotor vs housing collision sweep (3D meshes, every 1°): 0 overlaps, min gap 0.5 mm. • Crank effort: a 30 g die is lifted 103 mm, about 17 Nmm at the axle, under 1 N at the handle even with 2x friction. DICE: designed for standard polyhedral dice from 16 to 24 mm (d4 not tested; very small dice may slip past the arms). The 3D renders and the video use an 18 mm d6. Heavy metal dice have not been tested. PARTS (8 STLs, pre-oriented, no supports): body (back wall, shroud, back rail, tower ramps), facade (decor, runes, dwarf medallion, windows), brass front rail, copper rotor, axle, crank, handle, plinth. ASSEMBLY 1. Push the axle (head at the back) through the body's back wall and back rail. 2. Slide the rotor onto the axle inside the body: flat on the D-flat, flush face toward the front. 3. Press the front rail's 3 pegs into the facade, then press the facade onto the body's 10 pegs, with the axle passing through. 4. Press the crank onto the square axle end and the handle into the crank (a drop of glue on both is recommended). Set it on the plinth. NOT VERIFIED YET: not test-printed. Peg and press fits are designed with 0.35 mm (pegs) and 0.2 mm (crank square) clearance and may need sanding or glue. Rotor side clearance is 0.5–1.0 mm. Real dice bounce more than the quasi-static sim models, and the tumble randomness is not measured. Very light or round-edged dice may roll back slightly on the rail but the arm catches them. The dwarf-king medallion was made with AI tools (FLUX image -> TRELLIS 3D), then turned into a printable height-field relief. Everything else is parametric CAD.