Turn one kind of motion into another — with nothing but rigid bars and pins.

A gear multiplies torque. A linkage does something more surprising: it reshapes motion itself. Feed it a steady rotation and it hands you a nodding oscillation, a straight-line stroke, a scaled tracing of your hand, or a grip that clamps and holds itself shut — no gear teeth to cut, no involutes to calculate.

How to Create Mechanical Linkages is a hands-on guide for makers, students, and hobbyist engineers who want to move from copying mechanisms to designing them. It gives you exactly enough theory to make good decisions — then puts it straight to work in four fully dimensioned projects you can build and verify yourself.

The trap with linkages is that they're so easy to build, it's tempting to build them by trial and error — nudging pivots until something roughly works, then watching it bind at the worst moment, jam near dead center, or wear out a pivot in a week. A little theory turns that guesswork into design, and this book gives you just enough of it, in plain language, with clear diagrams on nearly every page.

Inside, you'll learn how to:

Count a mechanism's degrees of freedom and predict how it will move — before you cut a single part
Apply Grashof's criterion to know whether a link will spin all the way around or only rock
Read the transmission angle to avoid mechanisms that bind or stall
Design four-bars, slider-cranks, toggles, parallelograms, pantographs, and straight-line and quick-return mechanisms
Size pins, estimate forces, choose materials and hardware, and build joints that last
Take a design from sketch through CAD and prototyping into real, working parts

Four complete build projects — each with dimensioned plans, a full bill of materials, and a testing procedure:

Project 1 — An adjustable four-bar demonstrator that reconfigures into a crank-rocker, a change-point linkage, and a double-rocker
Project 2 — A slider-crank with selectable crank radius and interchangeable connecting rods
Project 3 — A drawing pantograph that produces true scaled copies of anything you trace
Project 4 — A low-force toggle clamp that locks itself over-center

Every worked example has been recalculated independently, every project's geometry checked mathematically, and every safety limit stated plainly — because this book is scrupulous about the difference between an educational teaching model and a load-rated machine.

Whether you're building a kinetic sculpture, a mechanical toy, a workshop clamp, or finally making sense of a kinematics course, this is the book that puts working mechanisms in your hands.