An assembly of timepiece parts assembled together with an adhesive at a temperature TA and to be repositioned when the adhesive is at a temperature TC. The adhesive includes a formulation, which at TC includes a mixture of polymer chains with pendant diene units X and coupling molecules including two dienophile end groups Y, wherein the X units and the Y groups are arranged to react with one another and to bond together with the Diels-Alder reaction at a temperature TDA and to regenerate with the retro-Diels-Alder reaction at a temperature TRDA, at TA forms a three-dimensional network, in which the polymer chains are linked to one another by the coupling molecules with the Diels-Alder reaction, where TA