I'm want to make a XT135 Carbon Fibre Tooling Prepreg mould.
I watched the training video and I noted it said to use the EP700 High Temp Epoxy Tooling Board for making moulds if you are using this directly with the XPREG® XC110 component prepreg. Which, I understand as you need it for the high temperature at cure.
 However, when you are making a XT135 Carbon Fibre Tooling Prepreg mould, do you need to make the master from the the EP700 High Temp Epoxy Tooling Board or could you use something like the PU240 or PU600 Density board (Or any other material) to make the master from as the Tooling prepreg doesn't go to such a high temperature.

It needs to be the epoxy tooling board.  PU based model boards inhibit the cure of epoxy based pre-pregs.  There is something in the chemistry of the two materials that means under the high temperature cure cycle, the PU inhibits the epoxy cure process. 

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant