
Investment Casting Process
The Thompson Investment Casting facility consists of state-of-the-art equipment and an experienced staff of skilled craftspeople and experts in the casting field. To help you understand if the investment casting process is the best choice for your needs, please review the step by step process below and call our engineers with any questions at 603.330.8670.
Tool Design and Manufacture

A wax injection mold is designed and built to produce castings per customer specifications.
Wax Production

A wax pattern of recyclable
material is produced from the
wax injection mold.
High Volume Production

Multi-cavity tools are used to expedite wax production.
Pattern Assembly

Thompson Investment Casting's unique method of gating and treeing systems assures sound castings at a minimum cost.
Shell Molding

The pattern assembly is systematically dipped into a ceramic slurry, coated with a refractory material and dried. The process is repeated until the desired thickness and strength is achieved.
Ceramic Shell Drying

Between coatings, the ceramic shells are dried
in an atmospherically-controlled environment.
Autoclave

Using regulated steam pressure, an autoclave melts and reclaims the wax from the ceramic shells.
Shell Curing

High temperature ovens cure and preheat the ceramic shells prior to pouring the molten metal.
Casting

Pre-heated molds are poured utilizing
a unique process which facilitates the production of thin walls and intricate detail while enhancing the surface.
Knock Out

The ceramic shell is removed and the cluster is cleaned
Cut Off

Castings are cut free
from the gating system.
Machining and Inspection

After cut off and gate removal, all secondary finishing operations are performed. Each casting is inspected according to customer specifications and requirements.