Binary Ink Developer Assembly Including A Guard Member Including A Conforming End Having A Concave Shape

A method of operating a binary ink developer assembly, the method comprising:

• receiving ink by a developer roller of the binary ink developer (BID) assembly;
• rotating a squeegee roller having a curved circumference forming a second arc to regulate a film thickness of the ink on the developer roller;
• transferring a portion of the ink from the developer roller to a photoconductive member;
• and
• reducing an amount of ink unintentionally exiting a housing of the BID assembly by a conforming end of a guard member of the BID assembly having a concave shape forming a first arc corresponding to a portion of the curved circumference of the squeegee roller such that the first arc and the second arc are concentric arcs.