Recent Blogs
Differential Transmission: Signed Side-speed Comparison
Compare carrier speed for same-direction and opposed-direction inputs to an ideal equal-side-gear differential. Torque, power flow and shifting behavior are not calculated.
Quick-Return Motion: Declared Crank-Arc Timing Ledger
Quick return mechanism explained — how the unequal forward and back stroke speeds up shaper, slotter and metalworking machines. Formulas, ratios and worked example.
Change Gear Motion Mechanism: How It Works, Diagram, Parts, Formula and Uses Explained
Explore a compound change-gear train with two external meshes and a shared middle shaft. Calculate input/output speed ratio from four tooth counts.
Ferguson's Mechanical Paradox Mechanism Explained: How It Works, Gear Diagram, Parts and Uses
Ferguson's Mechanical Paradox explained — how three loose gears on one arbor produce forward, reverse, and stationary outputs from a single input drive.
Variable Reciprocating Motion: Ideal Angle Comparison
Compare two defined angular sweeps from an offset-radius construction. The calculator does not solve complete quick-return geometry, slider travel, loads or a machine cycle.
Variable Circular Motion: Instantaneous Pitch-radius Ratio
Calculate one ideal no-slip gear contact state from input speed and two pitch radii. The tool does not generate non-circular pitch curves or a complete...
Sun and Planet Gear Mechanism Explained: How Watt's Epicyclic Drive Works, Parts, Diagram, Uses
Explore the sun-and-planet gear. Compare tooth counts, speed ratio and pitch geometry; equal gears give two sun revolutions per orbit in the ideal model.
Internal Spur Gear and Pinion: Pitch Geometry Calculator | FIRGELLI
Calculate ideal fixed-axis internal gear ratio, center distance and same-direction ring speed. Tooth interference, capacity and planetary motion are not calculated.
Geared Grip Tongs: Compound-Pinion Animation and Jaw-Travel Calculator
See how two coaxial pinions drive internal and external sectors to close a pair of jaws equally. Calculate matching radii, jaw rotation and tip gap.
External/Internal Sector Gears: Reversing-Motion Calculator | FIRGELLI
Explore a pinion driven alternately by external and internal gear sectors. Compare ideal forward and return travel, dwell and quick-return speed.
Spiral-Stud Conical Wheel: Variable-Speed Motion, Diagram and Calculator
Explore opposed conical wheels on parallel shafts. Animate one spiral-stud pass and calculate local speed ratio, stud spacing and pass time.
Worm-and-pinion Feed Roll Drive Mechanism: How It Works, Diagram, Parts, Formula and Uses
Explore a worm-driven feed roll. Calculate ideal reduction, feed per worm revolution and circumferential slack from an entered backlash angle.
Worm-and-pinion (modified): How the Globoid Hybrid Gear Works, Parts & Industrial Uses
Explore modified worm-and-pinion gearing. Compare ideal output speed, efficiency-adjusted torque and assumed load sharing without predicting gear strength.
Worm Screw Rack: Animation and Lead-Speed Calculator
Calculate ideal rack speed from screw lead and rpm, then compare torque-speed power and an efficiency-scaled thrust estimate. Self-locking is not predicted.
Vertical Drop Hammer: Ideal Energy and Momentum Comparison
Calculate ideal free-fall energy and speed, plus average momentum-change force for an entered stopping interval. Peak contact force, forging capacity and foundation loads are not...
Variable Vibrating Motion: Equal-frequency Amplitude Comparison
Compare two ideal harmonic amplitudes, peak-to-peak strokes and acceleration ratio at equal frequency. Actual acceleration, force and structural response are not calculated.
Variable Throw: Compare Two Ideal Traversing Strokes
Compare ideal crank-projection strokes for two entered radii, including their signed difference and percentage change. The tool does not design a live radius-adjustment or traverse...
Variable Sectional Motion: Two-interval Speed Comparison
Define two ideal speed intervals and compare their radius-derived speeds and angularly weighted average. The tool does not design sectional gears or transitions between speeds.
Elliptical Gear and Slotted Bar: Ideal Phase and Projection
Explore equal elliptical pitch curves with an illustrative slotted bar. Calculate ideal speed ratio and a separate cosine projection; actual bar motion and loads are...
Eccentric Crown Wheel and Pinion: Local Ratio Calculator
Explore an eccentric crown wheel and perpendicular pinion. Calculate a local ideal reduction ratio and lossless torque factor; complete tooth geometry and drive capacity are...
Sectional Spur Gear: Ideal Advance and Dwell Fractions
Explore toothed-sector engagement and a separate conceptual dwell lock. Compare ideal output advance and cycle fractions; engagement transitions and loads are not calculated.
Two-toothed Cam Pinion: Ideal Indexing-event Calculator
Compare ideal one-pitch indexing events from equally spaced effective teeth. Tooth contact, locking geometry and load capacity are not calculated.
Two-toothed Pinion: Ideal Intermittent Step Calculator
Explore an incomplete pinion and calculate ideal advance from active and driven tooth counts. The engagement slider changes illustrative timing only.
Differential Worm Wheels: Ideal Relative Rotation Calculator
Compare ideal relative motion of two coaxial worm-wheel sections with different tooth counts. The calculation does not establish tooth contact, torque or manufacturing feasibility.
Two-velocity Gears on One Shaft: Alternative Speed Comparison
Compare two selectable ideal gear paths to one output shaft. Check their ratios and the tooth-count condition for a shared center distance at common module.