An efficient tool design is crucial to the employment of RTM.

Compositech typically designs and manufactures RTM tooling from metal. Metals like aluminium and tool steel are used to make the best use of their properties like hardness, heat conductivity, thermal expansion and machinability.

Factorization

The thermal expansion of a typical carbon/epoxy laminate is very low compared to the metals used to cast it. Typically a RTM mould is heated to cure the component. The heating leads the metal tool to expand. To compensate for the difference in expansion the tool is made smaller than the parts final dimensions. As the tool expands up to the cure temperature it will gain the correct dimensions and the part will have the desired geometry as the resin solidifies at the cure temperature.

This process is called factorization and makes it possible to use dissimilar tool and part materials to obtain a correct part geometry.