Gear Train WorkbenchEngineering Education · Mechanisms & Gear Systems
All tiers unlocked
Name
Gears
Tools
Animation speed
Interactive gear sheet. Once it has focus: press N or P to select the next or previous gear; Arrow keys move the selected gear, hold Shift to move farther; F flips the selected gear between the front and back plane; M meshes it with the nearest gear; S stacks it onto a nearby shaft to form a compound pair; O attaches the motor and L attaches the load to the selected gear's shaft; Delete removes it. To add a gear, press number keys 1 through 9 to drop a gear size onto the sheet, or press a gear-size button in the toolbar then press Enter here.
Click or tap a gear size then click the sheet — or drag a size straight onto the sheet. Drag gears near each other to snap into mesh; drop one on a hub to stack it (compound). Gears mesh only with same-plane gears (F/B tag on each hub). No mouse? Press the ? for keyboard controls.
Motor
RPM
Torque (N·cm)
Ratio—
Output RPM—
Output N·cm—
Direction—
PASS
Show the working — stage-by-stage ratio math
Select a challenge to begin.
How to use the workbench
The two-plane rule — read this first. Every gear sits on a front or back plane, and gears only mesh with gears on the same plane. This is the single thing that stalls most people: two gears can look like they touch but won't turn each other if they're on different planes. Each gear is tagged F (front, light) or B (back, hatched) near its hub. A compound pair deliberately uses both planes — the large gear on the back, the small one on the front — so one stage can drive the next.
Build: click or tap a gear size in the palette then click or tap the sheet, or drag a size straight onto the sheet. Drag gears near each other and they snap into mesh. Drop a gear onto another gear's hub to stack it on the same shaft — that's a compound pair. A shaft holds at most two gears.
Power it: choose the Motor tool and click a gear to attach the motor — or drag the Motor button straight onto a gear. Do the same with the Load tool where you want to measure output.
Read it: the amber readout shows overall ratio, output speed, output torque, and direction. CW = clockwise. Open Show the working below the readout to see the ratio built up mesh by mesh — useful for checking where a prediction went wrong.
Meshed gears turn opposite directions; gears on one shaft turn together.
Ideal train: speed ÷ R, torque × R. Power in = power out.
Challenge mode: build the train, then enter your predicted output before you run. The workbench compares your prediction to the actual result — calculate first, then check. Each run re-hides the readout, so every attempt needs a fresh prediction; Predict again or Reset this challenge starts over. In a challenge the palette is limited to the gear sizes the brief lists.
Your progress is saved in this browser — completed challenges, attempts, and your name survive a refresh. Downloads (image, report, save file) are named with your name, the challenge, and the date, so type your name in the Name box first.
Keyboard (no mouse needed): focus the sheet (Tab to it), then:
1–9 drop a gear size onto the sheet
N/P select the next / previous gear; arrow keys move it (hold Shift to move farther)
M mesh with the nearest gear · S stack into a compound pair · F flip the front/back plane
O attach the motor · L attach the load · Delete remove the selected gear
Ctrl/⌘ Z undo · Esc cancels a tool
A screen reader announces the sheet and a running description of the train as you build. Turning on your system's reduce motion setting stops the gears from spinning while keeping the numbers live. The theme button switches between the light drafting-paper and dark Blueprint looks (your choice is remembered); exported images and reports always print ink-on-paper regardless.
Devices: use a laptop, desktop, or full-size tablet. A phone screen is too small for the drawing area — a phone layout is planned but not here yet.