What are the three components of a standard feature control frame?

What are the three components of a standard feature control frame?

• A. Geometric characteristic symbol, tolerance value, and datum references.
• B. Geometric characteristic symbol, datum references, and material specification.
• C. Geometric characteristic symbol, tolerance value/modifier, and datum references.
• D. Datum references, tolerance modifier, and projected tolerance.

Answer: (C)

In GD&T, a standard feature control frame is built from three essential parts: the geometric characteristic symbol, the tolerance value with any modifiers, and the datum references. The geometric characteristic symbol tells you which geometric property is being controlled (for example, position, perpendicularity, or flatness). The tolerance value, and any modifiers attached to it, specify how tight the control is and how the tolerance behaves (such as using a cylindrical tolerance zone or applying a maximum material condition). The datum references establish the measurement framework—the datum features that the control is referenced to and the order in which they define the coordinate system for the feature. So you’re looking for a frame that clearly shows what is controlled (the symbol), how tight the control is and any special rules (tolerance value with modifiers), and what the frame is referenced to (datum references). The other options introduce material specifications or omit the key symbol, which is why they don’t fit as the three components.

In GD&T, a standard feature control frame is built from three essential parts: the geometric characteristic symbol, the tolerance value with any modifiers, and the datum references. The geometric characteristic symbol tells you which geometric property is being controlled (for example, position, perpendicularity, or flatness). The tolerance value, and any modifiers attached to it, specify how tight the control is and how the tolerance behaves (such as using a cylindrical tolerance zone or applying a maximum material condition). The datum references establish the measurement framework—the datum features that the control is referenced to and the order in which they define the coordinate system for the feature.

So you’re looking for a frame that clearly shows what is controlled (the symbol), how tight the control is and any special rules (tolerance value with modifiers), and what the frame is referenced to (datum references). The other options introduce material specifications or omit the key symbol, which is why they don’t fit as the three components.