How to Read a Fabrication Blueprint

Written by corey morris
  • Share
  • Tweet
  • Share
  • Pin
  • Email
How to Read a Fabrication Blueprint
You'll need to know how to read fabrication blueprints before welding steel. ( Images)

Many buildings today are composed out of steel material. Each piece of steel is distinguished from any other piece by what is known as a piece mark. Piece marks give each piece of steel a unique identity with varying dimensions. Using blueprints to construct a steel building may be difficult to understand at first. To correctly piece together steel, you must know how to read basic fabrication blueprints.

Skill level:

Things you need

  • Fabrication blueprint
  • Table

Show MoreHide


  1. 1

    Lay the blueprint flat on a table. Look for the legend on the map that shows the sizes of the steel you need to complete your project. This information can usually be found in the lower right side of the prints in a little box.

  2. 2

    Find the piece marks. Piece marks are paired with each drawing and are designated by at least one capital letter and a number, such as 2A. The material listing will also provide a breakdown of each piece mark on the drawing.

  3. 3

    View one of the steel pieces drawn on the print. Measurements for steel are taken from left to right with the dimensions from the beginning of the steel or the work point (wp) which may be used by a detailer to mark a specific point to begin working from. Work points are more common with complicated pieces of steel.

  4. 4

    Pay attention to arrows on the blueprint that point to any additional pieces. Angles and plates that connect to the main steel piece are often labelled using numbers and lower case letters. Angles are marked with an "a" and plates with a "p."

  5. 5

    Locate any holes that need to be drilled. Dimensions for holes are labelled above the drawn steel pieces with measurements provided at the top of the main piece of steel.

  6. 6

    Look for any other boxes near the print's legend box. There may be other drawing notes including painting details or other information located on the fabrication prints. This box might also contain the number of bolts necessary to complete the project.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the site, you consent to the use of cookies. For more information, please see our Cookie policy.