Recent Blogs
Rack and Pawl: Declared Index-Pitch Ledger
How a Rack and Pawl mechanism converts reciprocating motion into one-way linear indexing — design rules, formulas, and real applications in lift jacks and presses.
Lever to Slotted Rack via Two Hooked Pawls: How This Indexing Mechanism Works, Parts & Uses
See a driving pawl advance a slotted rack while a holding pawl retains each step. Calculate ideal cumulative travel from slot pitch and successful index...
Drop-and-Pawl Intermittent Rotation: Indexing Calculator | FIRGELLI
Compare star-wheel step angle, events per revolution and average event frequency. Brown movement 63 supplies the historical sequence; the current illustration does not solve contact...
Bent-spring Driver with Strong-spring Catch: How the Mechanism Works, Parts, Formula, and Uses
Explore a bent spring on a rotating carrier engaging an intermittent ratchet through a fixed catch. Compare spring rates, preload and catch seating force.
Intermittent Motion: Geneva Index and Dwell Calculator | FIRGELLI
Compare ideal Geneva step and index/dwell fractions, including an overlap warning for equally spaced pins. Physical multi-pin compatibility is not established.
Watch Train: Ideal Compound Gear-ratio and Speed Calculator
Follow a barrel-to-escape going train and calculate ideal speeds from four entered ratios and barrel period. Tooth geometry and torque are not calculated.
Watch Regulator: Ideal Hairspring Length and Frequency Comparison
Explore how effective hairspring length affects an ideal balance oscillator. The calculated rate change is an estimate, not movement calibration.
Riefler Double Escape Wheel: Side View and Angle Comparisons
See the coaxial Riefler driving and locking wheels in side view. Compare entered angles and ideal tooth pitch without treating them as clock setup targets.
Riefler Double Escape Wheel: Front View and Reference Comparisons
Explore the distinct driving and locking wheels of a Riefler escapement. The accompanying number and angle comparisons do not predict contact or clock rate.
Simple Pendulum: Period, Gravity and Finite Amplitude
Calculate ideal simple-pendulum length from full period, gravity and swing amplitude. Compare finite-amplitude and small-angle results and the half-period beat.
Mercurial Compensation Pendulum: First-Order Thermal Balance
Explore historical mercurial pendulum compensation and a first-order balance between rod growth and mercury center-of-gravity rise, including jar expansion.
Harrison Maintaining Power: Energy and Equivalent Spring | FIRGELLI
Compare winding-interval energy, train power and an equivalent linear spring. Includes explicit torque and travel limitations; not a spring specification.
Endless-chain Maintaining Power (clock) Mechanism Explained: Parts, How It Works, and Uses
Explore endless-chain maintaining power in a weight-driven clock. Compare driving and tension weights while the drive remains connected during winding.
Electric Winding Device Mechanism: How It Works, Diagram, Parts, Calculator and Uses Explained
Explore a motorized clock winder and compare a chosen friction-clutch torque threshold with reference torque and winding demand.
Double Tri-toothed Pendulum Escapement Mechanism: How It Works, Parts, Geometry & Uses Explained
Explore the double tri-toothed pendulum escapement with alternating locks, a triangular arbor and curved pallets. Calculate release timing and tip motion.
Cycloidal Pendulum Movement Explained: How Huygens Cheeks, Tautochrone Geometry, and Isochronism Work
See how cycloidal cheeks guide a constant-length pendulum cord. Calculate ideal beat length and compare an ordinary circular pendulum’s clock error at two amplitudes.
Compensation Balance Mechanism Explained: How the Bimetallic Wheel Corrects Temperature Error
How a Compensation Balance corrects temperature rate error in mechanical watches and chronometers — bimetallic theory, formulas, worked example, and design tradeoffs.
Balance-wheel Escapement Mechanism: How It Works, Parts, Diagram, Formula and Calculator
Explore a lever escapement’s locking and impulse sequence. Convert beat rate to full period and calculate ideal hairspring stiffness and stored balance energy.
Going Train Calculator: Clock Gear Ratios and Speeds | FIRGELLI
Calculate speeds and barrel period through four clock-train gear stages. Explore direction reversals and distinguish gear ratios from escapement timing.
Wheel Train Mechanism Explained: How It Works, Gear Ratio Formula, Parts, and Horology Uses
Explore three ideal gear-train stages. Compare the combined speed multiplier, output rate, revolution time and lossless torque ratio.
Typewriter Action: Schematic Motion and Displacement Comparison
Explore a key, typebar and escapement sequence. Compare scaled displacement and average speed using an entered ratio and time; actual impact and typing rate are...
Tourbillon: Rotating Cage and Timing Calculator
Explore the rotating cage and convert balance frequency, cage period and elapsed time into timing quantities. The calculator does not predict watch accuracy.
Grand Piano Action: Declared Travel and Let-Off
How a piano key and action mechanism works — leverage ratio, hammer escapement, and repetition timing for piano builders, technicians, and restoration shops.
Mechanical Timer: Escapement and Gear-Ratio Calculator
Explore an ideal mechanical escapement and calculate duration, cycle count and output speed from tooth count, full-cycle frequency and gear ratio.
Hairspring: Balance Frequency and Energy Calculator | FIRGELLI
Compare ideal hairspring frequency, beats per hour, spring energy and rate change from stiffness trim. Includes a slowed balance-and-spring animation.