Recent Blogs
Leg-of-mutton Sail
How a leg-of-mutton sail works — geometry, driving force, rigging tradeoffs, and a worked example for sizing a small-craft mainsail by wind speed.
Lateen-rigged Felucca
Lateen-rigged felucca explained — how the triangular sail and slanted yard drive Nile cargo boats upwind, with rig geometry, drive force formulas and a worked...
Floating Dry-dock
Floating dry-dock explained — how ballast tanks, pontoons and wing walls lift ships for hull repair, with formulas, worked examples and shipyard applications.
Stevedore Knot
Learn how the Stevedore Knot works as a stopper knot for sailing rigs and load handling, with sizing rules, worked examples, and comparison to figure-8...
Steam Fire Engine
Steam Fire Engine explained — how the boiler, pump, and steam cylinder deliver firefighting water pressure, with a worked example for municipal brigades.
Single Eccentric Reversing Gear
Single Eccentric Reversing Gear explained — how Stephenson-era engineers reversed steam locomotives with one eccentric, slip-link, and gab hook. Diagrams, math, examples.
Ship's Steering Gear
How a ship's steering gear works — hydraulic rams, rapson slide geometry, torque sizing, and real examples from cargo ships, ferries and naval vessels.
Screw Anchor
Screw anchors hold signs, guardrails and utility poles by threading helical plates into soil — here's how they work, the holding-capacity formula and field examples.
Schooner Rig
Schooner rig explained — how the fore-and-aft two-mast layout drives offshore sail-training vessels, with sail-area math, worked example, and trade-offs.
Pivoted Steps
Pivoted steps swing out of the way under load or for storage. Learn how engineers size them for buses, fire trucks, RVs, and rail platforms.
Pirogue
Pirogue design explained — hull geometry, paddling load, stability limits, and real-world use from Louisiana bayous to West African fishing fleets.
Ice Bicycle
How an Ice Bicycle works — studded tyres, ski conversions, and frame geometry for winter cycling. Real numbers, real builds, and sizing guidance for commuters.
Fleming Loop
Fleming Loop explained — how this navigation deviation routes traffic around fixed obstacles, with formulas, worked examples, and real road-design applications.
Vertical Bucket Paddle Wheel
Vertical Bucket Paddle Wheel explained — how the buckets dip, lift and discharge water, the head-vs-flow formula, and real installs in irrigation and micro-hydro.
Two-masted or Dipping Lug
How the two-masted dipping lug rig works, why crews dip the yard at every tack, and where it still sails today on working boats and...
Topsail Schooner
How a Topsail Schooner works — fore-and-aft rig with square topsails on the foremast, sail plan math, real vessels like the Pride of Baltimore II,...
Timber Hitch
Timber Hitch knot guide for arborists, riggers, and boatbuilders — how it grips logs, holding capacity, tying steps, and when to choose it over alternatives.
Thrust Bearing
Thrust bearings carry axial loads in automotive transmissions, marine propeller shafts and machine tools. See how they work, the math, and selection rules.
Three-quarter Lug Rig
Three-quarter lug rig explained: how the yard sets, why the tack lands forward of the mast, and how dinghy builders size halyard and downhaul tension.
The Cutter
How a Cutter works as a fast single-masted vessel for pilot transfers, revenue patrol and coastal interception. Hull form, rig, sizing and worked example.
Ten-wheel Freight Locomotive
Ten-wheel freight locomotive explained — wheel arrangement, tractive effort formula, and real-world hauling examples from steam-era American railroading.
Swinging Oar-lock
How a Swinging Oar-lock works, why rowing crews use it, and how to size pin offset and horn height for shells, dinghies, and traditional craft.
Swinging Ball-bearing Bicycle Pedal
Swinging ball-bearing bicycle pedals pivot under the rider's foot to reduce ankle strain. See how they work, the bearing layout, and where they fit on...
Submarine Lamp
Submarine lamps mark navigable channels and submerged hazards underwater. Learn how the sealed lens, ballast, and mooring work together for harbour authorities.
Street-car Sand Box
How a streetcar sand box works — gravity-fed sanders boost rail adhesion on wet, leafy, or icy track. Numbers, sizing, and real transit examples inside.