What is the minimum radius of a field bend on trade size 1 1/4 RMC?

The minimum radius for a field bend on trade size 1 1/4 Rigid Metal Conduit (RMC) is indeed 8 inches. This specification ensures that the bending of the conduit does not compromise its structural integrity, which is crucial in maintaining the performance and safety of electrical installations.

Field bends are made to allow the conduit to change direction, and adhering to the minimum radius is essential to avoid kinks or damage to the conduit. For rigid metal conduits, the National Electrical Code (NEC) and other relevant standards provide guidelines on these minimum bend radii to ensure compliance and safety.

When making bends, particularly in RMC, it's critical to consult the appropriate code references, as they dictate the necessary minimums based on conduit size to mitigate risks associated with tight bends which can cause stress and potential failure in the conduit system.