Preparing the CO2 silicate cores for casting the Maserati long pulley half. Rather unusual cores that I would have preferred to have made using the shell process as it produced stronger and less outgassing cores but that would have required metal core boxes - not justifiable for just 2 off castings.
The blue wash put on the "doughnut" cores is "Isomol 185" by "Foseco" It is an alcohol based zircon wash and it helps to improve the otherwise rough surface finish that silicate cores give
Part 2, coming soon, shows these cores being used to make the Aluminium castings