Investment casting is the modern embodiment of the very ancient lost wax casting.
The process starts by making a wax model of the desired component. Here the wax part is injection molded.
Wax patterns are assembled onto a common wax sprue
The assembled tree is then coated with a refractory slurry.
The slurry is then covered with a dry refractory powder. This is repeated many times.
An investment of refractory material is built up.
The wax is melted out, and the ceramic investment is fired to form a strong mold.
The mold is then heated further and poured.
The investment is then removed mechanically.
The individual parts are then separated and finished.