What effect does the L modifier have on a position tolerance?

What effect does the L modifier have on a position tolerance?

• A. It ties the tolerance to the maximum material condition of the controlled feature.
• B. It eliminates all material condition considerations from the tolerance.
• C. It ties the tolerance to the least material condition of the controlled feature.
• D. It ties the tolerance to the least material condition only for holes.

Answer: (C)

The concept being tested is how a GD&T modifier changes a position tolerance by tying it to a material condition. The L modifier specifically binds the position tolerance to the least material condition (LMC) of the controlled feature. This means the tolerance is interpreted with the feature in its LMC state: for a hole, that’s the smallest hole size; for a shaft, the largest diameter. By anchoring the positional requirement to LMC, the tolerance reflects the worst-case material situation around the feature, which helps ensure proper fit when material removal or size variation occurs. As the actual size moves away from LMC, the practical effect is that the allowable positional variation is governed by that LMC reference, altering how strict the position must be to still be acceptable. The other options don’t fit because the L modifier does not remove material condition considerations, does not reference MMC, and is not limited to holes.

The concept being tested is how a GD&T modifier changes a position tolerance by tying it to a material condition. The L modifier specifically binds the position tolerance to the least material condition (LMC) of the controlled feature. This means the tolerance is interpreted with the feature in its LMC state: for a hole, that’s the smallest hole size; for a shaft, the largest diameter. By anchoring the positional requirement to LMC, the tolerance reflects the worst-case material situation around the feature, which helps ensure proper fit when material removal or size variation occurs. As the actual size moves away from LMC, the practical effect is that the allowable positional variation is governed by that LMC reference, altering how strict the position must be to still be acceptable. The other options don’t fit because the L modifier does not remove material condition considerations, does not reference MMC, and is not limited to holes.