Help Guide

Shell Inner Diameter — Sets the physical size of the mill (1–12 m). Larger mills spin slower (in RPM) to achieve the same percentage of critical speed.

Rubber Lining — Thickness of the wear-resistant rubber liner (0, 6, or 12 mm). Reduces the effective interior volume.

Shell Plate Left / Right — Thickness of the steel plate behind the rubber (30–150 mm each), set independently for the leading and trailing sides of each lifter so the plate top ramps into an angled ball-tumbling surface between lifters.

Shell Plate Lip — Reduced plate thickness under each lifter (10 or 15 mm), producing the stepped cross-section.

Height — How far lifters protrude from the shell (50–400 mm). Taller = balls lifted higher.

Leading Edge Height (LEH) — Height of the vertical leading face (30–165 mm). Lower LEH angles more of the face.

Width — Circumferential width of each lifter at its base (100–400 mm).

Face Angle — Rake angle of the leading face, from vertical (0–45°). Steeper = more direct lifting.

Count — Number of lifters around the circumference (6–60).

The S:H guidance flags whether your spacing-to-height ratio lands in the working band. Per Malcolm Powell the target is aimed at mid-life of the liner — the suggested row count places the new liner at the lower edge of the band so it wears up through the target. Enable the application selector and progressive wear slider in Default Settings to apply SAG / Primary / Secondary presets.

Total Charge Level — Combined fill of media plus ore (0–45% of the mill cross-section).

Grinding Media Level — The steel-ball portion (clamped to ≤ total). Ore is the remainder.

Media / Ore Over-seed — Multipliers (1–3×) that over-seed at load time so the settled pile packs up to the target charge line.

Keep the total charge under 45% — above this, shoulder formation and grinding efficiency suffer.

Grinding Media PSD — Custom mix of steel-ball diameters and volume fractions. Add rows; the percentages should total 100%.

Ore PSD — Custom mix of ore particle diameters and volume fractions, set the same way.

Media renders grey (steel); ore renders brown. Multiple sizes fill interstitial spaces for better grinding efficiency.

% Critical Speed — How fast the mill rotates relative to its critical speed (40–100%), where centrifugal force overcomes gravity.

Below 65% = cascading (green). 65–82% = cataracting (amber, optimal). Above 82% = centrifuging (red, avoid).

RPM — Calculated automatically from diameter and speed percentage, shown in the floating panel.

Media-to-Media — Grip between steel balls. Higher = the ball bed rotates more as a body.

Media-to-Boundary — Grip between media and the liner/lifters. Higher = the charge is dragged further up the shell.

Ore-to-Ore — Grip between ore particles, affecting how the ore bed shears and interlocks with media.

Ore-to-Boundary — Grip between ore and the liner/lifters. Higher = ore carried higher into the cataracting zone.

Each friction slider runs 0.05 (slippery) → 0.7 (sticky). Changes take effect live — no need to re-seed.

Seed Ore / Seed Media — Load the charge. Particles fall and pack under gravity ("SETTLING CHARGE…"), then "CHARGE READY — press Play" appears.

Play / Pause — Start and stop rotation. Pause freezes the charge; resume continues from the same state.

Charge Lines — Toggle Total (green), Media (orange), and Ore (light blue) to overlay each component's target free-surface chord.

Changing geometry or charge parameters clears the charge — re-seed to reload it.

Pan / Zoom — Drag to pan, scroll or pinch to zoom.

Fit to Screen — Resets pan/zoom to the default framed view.

Full Screen — Enters browser fullscreen for unattended booth operation; press again to exit.

Reset — Restores the saved default parameters (shared across all users via Default Settings) and clears the charge.

Geometry — Opens an inspector overlay showing exact layer dimensions and labels.

Charge Lines — Toggle Total (green), Media (orange), and Ore (light blue) to overlay each component's target free-surface chord on the mill.

Toe & Shoulder Markers — A blue block marks the toe (impact / landing side) and an orange block marks the shoulder (lift-off / rising side) of the largest media, sized to the largest ball diameter.

Tracer Lines — Fading yellow lines follow a subset of the largest media balls from shoulder to toe, showing the cataracting trajectory. Use the tracer-fraction control (25 / 50 / 75 / 100%) to choose how many balls to trace.

Liner Damage Alerts — When a large media ball strikes the liner above 3.5 m/s, an expanding red flash marks the impact point and an alert reports the severity band: Medium (3.5–4.5 m/s) or High (≥4.5 m/s), with the worst impact speed in the dominant band.

Theoretical Trajectory — The Theory toggle overlays a red parabolic curve and impact square for the ideal single-particle flight from the lifter shoulder (MillTraj-style), plus theoretical shoulder/toe markers from the charge level and speed.

Charge Motion — Cascading, Cataracting, or Centrifuging (derived from speed), shown as a coloured badge in the floating panel.

Charge Level & Media/Ore split — Live percentages shown in the floating panel.

Derived Values — Effective diameter/radius, cross-sectional area, charge angle, chord, heights, critical speed, and linear speed — computed from the current parameters.

Particle Counts — Per-size media and ore counts plus the renderable total.

Mill Volume — The true free interior volume of a 1 m slice (excluding heads and liners), shown in the floating panel.