Drawing a Free BodyThe five-step method that prevents most statics errors.Mechanical EngineeringOne body, every force on it, nothing else.1Cut the body outDraw the part alone. Every contact you cut becomes a force.2Add the applied loadsWeight at the centre of mass, plus every external load.3Replace each supportOne force per motion it blocks, a moment if it blocks rotation.4Fix a sign conventionPick positive x, positive y and a positive sense for moments.5Count the unknownsThree equations in 2D, six in 3D. More unknowns needs stiffness.A force the body exerts on something else never appears on its owndiagram.Drawing a Free Bodylearnposters.com
Drawing a Free Body — printable engineering wall chart from LearnPosters. Free vector PDF, US Letter and A4.

Drawing a Free Body, step by step

One body, every force on it, nothing else.

  1. Cut the body outDraw the part alone. Every contact you cut becomes a force.
  2. Add the applied loadsWeight at the centre of mass, plus every external load.
  3. Replace each supportOne force per motion it blocks, a moment if it blocks rotation.
  4. Fix a sign conventionPick positive x, positive y and a positive sense for moments.
  5. Count the unknownsThree equations in 2D, six in 3D. More unknowns needs stiffness.

A force the body exerts on something else never appears on its own diagram.

Questions about the Drawing a Free Body poster

What’s on the Drawing a Free Body poster?
5 numbered steps. One body, every force on it, nothing else. Cut the body out — Draw the part alone. Every contact you cut becomes a force.; Add the applied loads — Weight at the centre of mass, plus every external load.; Replace each support — One force per motion it blocks, a moment if it blocks rotation.; Fix a sign convention — Pick positive x, positive y and a positive sense for moments.; Count the unknowns — Three equations in 2D, six in 3D. More unknowns needs stiffness.. A force the body exerts on something else never appears on its own diagram.
Who is the Drawing a Free Body poster for?
Drawing a Free Body belongs to the Mechanical Engineering section rather than to a school year, because engineering is not something one grade owns. Anyone learning statics & dynamics can pin it up — a beginner, a student mid-course, or someone revising years later.
When should you use the Drawing a Free Body poster?
Before you write a single equilibrium equation. No diagram, no marks. A wall chart earns its place by being glanceable from where the work is happening, so Drawing a Free Body belongs on the wall where that engineering work actually happens, within glancing distance, rather than filed away.
What other posters go with Drawing a Free Body?
Supports & Reactions, Finding a Centroid and Dry Friction sit alongside Drawing a Free Body in the Mechanical Engineering section. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.Supports & ReactionsFinding a CentroidDry Friction
Is the Drawing a Free Body poster free to download and print?
Yes. Drawing a Free Body downloads as a free PDF with no account, no email and no watermark, like everything else in the Mechanical Engineering section. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
What size does the Drawing a Free Body poster print at?
Drawing a Free Body is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Drawing a Free Body loses nothing.Printing guide

Related posters

Charts that sit alongside Drawing a Free Body on the same wall.

Browse every Mechanical Engineering poster, or start from the full catalogue.