Knowing the mechanical properties of UV-curable resins at cryogenic conditions is important to ongoing fusion-energy research and to emerging aerospace applications. The tensile and interfacial shear strengths of two commercially available UV-curable resins were measured at room-temperature and cryogenic conditions for both bulk and reduced (subnanoliter) specimen volumes. The tensile properties of cured specimens are remarkably sensitive to both testing temperature and specimen size. For one type of resin, the cold (-150 degrees C) tensile strength of subnanoliter specimens is similar to 9x larger (179 +/- 19 MPa) than bulk values at room temperature. The interfacial shear strength between SiC fibers and small volumes of resin volumes is comparable to the bulk, room-temperature tensile strength, but it varies over a wide range at -150 degrees C (15-53 MPa). All resins were fully cured, and an analysis of fractured surfaces revealed microstructural features. The enhanced strength in microscopic specimens may be related to inhomogeneous stress fields that develop during cure. (C) 2014 Wiley Periodicals, Inc.