Abstract: An improved coupling for the core of a heated rotatable member and the support and drive for the core. The core has a surface including a first wall and a second wall spaced from and angularly disposed to the first wall which define a groove in the surface. Drive means, such as an end gudgeon, is mounted in juxtaposition with the groove for supporting and rotating the core. The coefficient of thermal expansion of the drive means is different from that of the core. A coupling, which compensates for unequal thermal expansion or contraction of the drive means and the core, has a first portion engaging the drive means to maintain support and rotation of the core by the drive means. The coupling further has a second portion extending at least partially into the groove spaced from the first wall to accommodate for movement between the drive means and the core resulting from unequal thermal expansion or contraction because of temperature change.