The COMETA project aims at solving the following problems of SMEs European machine tools manufacturers: -Get high “Thermal” stability, in order to minimise thermally-induced errors arising from thermal deformations of the machine structures caused by internal/external heat sources. -Get high “Dynamic” stability, in order to minimise vibration (forced and chatter) and inertial effects of machine structures. COMETA intends to reach this goals through the integration and tailoring (to specific need machinery sector) of innovative materials, and exploiting a double-side solution: -Novel and mouldable polymeric short fibers “Compound” (SFC) to be used to produce complex parts (flanges, inserts, …) of machine that are use to interface mechanical components (e.g. motors, guideways, spindle, ….) with the rest of the structure made of composite. The proposed SFC is composed of reinforcement (glass or carbon) with short fibres, powdered or impregnated with proper % in volume of thermoset or thermoplastic resin. Switching from metal interfaces (aluminium/steel) to Compound material would bring: extremely lower thermal drift; weight reduction, thus lower energy consumption and lower part inertia; no galvanic corrosion. -Aluminium matrix composite (AMCs) materials to design and realise low-weight (and hot) parts of machines with excellence mechanical performance (e.g. spindle case, bearing spacer, multi-spindle head, motor base, etc.). The reinforcement in AMCs could be in the form of continuous/discontinuous fibres, whisker or particulates. Properties of AMCs can be tailored to the demands of different Machine tool applications by suitable combinations of matrix, reinforcement and processing route. The major advantages of AMCs compared to unreinforced materials are as follows: improved stiffness to weight ratio; improved high temperature properties; controlled thermal expansion coefficient; improved abrasion and wear resistance; improved damping capabilities