What Does %% C Mean in AutoCAD?

In AutoCAD, the %%C symbol is used to represent the diameter of a circle or a cylindrical object. It is a widely used symbol in engineering and architectural drawings to indicate the size of circular features.

Understanding the %%C Symbol

The %%C symbol is derived from the mathematical notation for representing diameter, which is denoted by the letter “D”. However, due to limitations in early computer systems and ASCII character sets, a universally accepted symbol for diameter was needed. The double percentage sign (%%) followed by the letter “C” was chosen as a substitute for “D”.

Usage in AutoCAD

In AutoCAD, you can use the %%C symbol in various ways:

  • Dimensioning: When creating dimensions for circular objects such as circles or cylinders, you can use the %%C symbol to indicate diameter. For example, if you have drawn a circle with a radius of 10 units, you can create a dimension using the text “10%%C“. This will display the dimension as “10 units” with the %%C symbol indicating that it represents diameter.
  • Text Annotations: You can also use the %%C symbol in text annotations or labels to clearly indicate that a value represents diameter.

    This helps avoid any confusion when reading or interpreting drawings.

  • Symbol Blocks: In some cases, engineering and architectural symbols blocks may already include the %%C symbol. These blocks are pre-defined sets of geometrical shapes and symbols that can be inserted into your drawing. If such blocks are available, you can directly use them to represent diameters without manually adding the %%C symbol.

Tips for Using %%C Symbol Effectively

Here are some tips to ensure the effective use of the %%C symbol in AutoCAD:

  1. Consistency: Be consistent in your usage of the %%C symbol throughout your drawing or project. This helps maintain clarity and consistency in communication.
  2. Clear Annotations: When annotating dimensions or adding labels, ensure that the %%C symbol is clearly visible and not obscured.

    Use appropriate font sizes and formatting to make it stand out.

  3. Legibility: Pay attention to the legibility of the %%C symbol, especially when printing or scaling drawings. Ensure that it remains clear and distinguishable even at smaller sizes.

In Conclusion

The %%C symbol is an essential element in AutoCAD for representing diameter. Understanding its usage and implementing it effectively can enhance communication and clarity in engineering and architectural drawings. By using the appropriate styling elements such as underlining, bold text, and proper

,

, etc., you can make your annotations visually engaging and organized, improving overall readability.