What factor determines the minimum space between rivets?

The minimum space between rivets is primarily determined by the diameter of the rivets being used. This is because the spacing must allow for sufficient strength and structural integrity of the assembly while preventing issues such as material failure or overlapping of the rivet heads. If rivets are placed too closely together, it can lead to problems, such as localized stress concentrations, which may decrease the effectiveness of the joint.

Moreover, proper spacing helps to ensure that each rivet can be properly set and that the load is evenly distributed across all rivets in the joint. Using a spacing rule based on the rivet diameter ensures that the mechanical properties are maintained and that the rivets can perform their intended function without compromising the integrity of the materials being joined.

Other factors mentioned, such as the length of the rivet, thickness of the metal sheets, and type of staking used, can influence the overall rivet installation and its suitability for a particular application, but the nominal diameter of the rivet itself is the critical factor that dictates how closely they can be spaced in a given joint configuration.