The maker in question makes intake manifolds for Ford throttle bodies and demonstrates an excellent technique for making them in a small shop.
In the technique, the mould patterns are CNC machined from a solid block of polystyrene, with all the necessary gates to feed the aluminium into the mould.
The mould parts are then sprayed with a surfactant and dip-coated in a refractory slurry to produce a satisfactory coating.
The coating is then placed in a moulding pan fitted with a pneumatic turbine vibrator, to allow sand to be introduced.
A neat offset pouring cup is then added to the top of the structure and packed in with more sand.
Finally, the demoulding is carried out by simply dumping the whole stack onto the drive and throwing the extracted casting into a snow bank.
