2. The legend
The legend is a key part of any manufacturing blueprint.
It provides essential information about the blueprint symbols, dimension lines, and colors used on the blueprint. This information is necessary for anyone who needs to interpret the blueprint. The legend typically includes the following information:
- The meaning of each blueprint symbol, line, and color used
- The scale of the blueprint
- The units of measurement used on the blueprint
- Any other relevant information that would help someone interpret the blueprint correctly
Without a legend, a blueprint would be harder to read and understand.
3. The grid
The grid is a fundamental part when looking to draw blueprints.
It provides a consistent, reliable framework for building the rest of the blueprint. Without the grid, blueprint reading would be little more than a collection of random parts and pieces. The grid consists of three key components:
- A network of horizontal and vertical blueprint lines that crisscross the page
- A series of evenly spaced dots that are placed along these dimension lines
- A series of numbers and letters that are assigned to specific locations within the grid
Together, these three components create a coordinate system that can be used to precisely locate any point on the page.
This is incredibly important in manufacturing, where even the slightest error can have disastrous consequences. The grid provides a reliable, consistent way to locate points on a blueprint.
4. The scale
The scale in a manufacturing blueprint is the ratio between the size of an object on the blueprint and the object’s actual size.
The scale is usually expressed as a fraction or a ratio, such as 1:10 or 1/10. This means that for every unit of measurement on the blueprint, there are 10 units of measurement on the actual object. The scale can also be expressed as a percentage, such as 10%.
This means that the object’s size on the blueprint is 10% of the actual size of the object.
Blueprint scales are used to ensure that objects are manufactured to the correct size. Three scales are commonly used in understanding blueprints:
- English scale
- Metric scale
- Architectural scale
The English scale is the most common scale used to draw blueprints.
It is based on the imperial measurement system, which uses inches and feet as its units of measurement. The English scale is typically expressed as a ratio, such as 1:12 or 1/12. This means that for every inch on the blueprint, there are 12 inches on the actual object.
The metric scale is based on the metric system of measurement, which uses meters and centimeters as its units of measurement. The metric scale is typically expressed as a percentage, such as 10%. This means that the object’s size on the blueprint is 10% of the actual size of the object.
The architectural scale is used to draw blueprints for buildings. It is based on architectural drawings, which use feet and inches as its units of measurement. The architectural scale is typically expressed as a ratio, such as 1:50 or 1/50.
5. The notation
Notation is a set of symbols and other markings used to convey information on blueprints and other technical drawings.
Reading engineering drawings typically includes various types of notations, such as dimensions, tolerances, surface finishes, raw materials specifications, and more. Knowing how to read and understand the notation on a manufacturing blueprint is essential for anyone who needs to interpret or use the drawing. With that in mind, let’s look at some of the most common types of notations that you’ll find on blueprints.
Dimensions are the most basic and essential type of notation on any blueprint or technical drawing.
It provides key information on the size, shape, and location of the various features shown on the drawing.
Surface finishes are another important notation found on blueprints.
These symbols indicate the required finish for various surfaces on the part or product.
Tolerances are numerical values that specify the acceptable range of variation for a given dimension or feature when making an item.
They’re typically used to ensure that parts fit together correctly and function as intended.
Material specifications, which can also be referred to as a bill of materials (BOM), are a type of notation that provides information about the materials that should be used to make the part or product.
This includes information such as the required material grade, hardness, thickness, etc. These are just a few of the most common types of notations you’ll find on blueprints. By understanding what each type of notation means, you’ll be able to interpret the drawing correctly and ensure that the part or product is made properly.