Investment Casting

Also known as precision casting, investment casting is a lost wax casting process mainly used for producing metal parts with relatively low production quantities or for products that is constantly and rapidly changing. The process is perfect for casting mission critical parts that is highly complex while having a high level of accuracy. Casting products manufacturers with years of experience can produce complicated shapes that would be difficult or impossible with other casting methods which can dramatically reduce the need for secondary machine processes.

At Irwin, we cast up to 2 types of ferrous and non-ferrous metal alloys. The investment casting manufacturer we partner with specializes in 3 types of metals. We also offer precision machining with CNC machines from 3 axis to 5 axis to machine to final end product.

Step 1

Tooling Design and Tool Making

A tooling is designed and made according to the customers’ drawings.

Step 2

Wax Injection

Wax is injected into the die to create a wax pattern.

Step 3

Wax Pattern Assembly

Wax patterns are assembled onto the runner and into a finished tree which is ready to be dipped.

Step 4

Slurry Coating

Wax tree is dipped into a hight-grade slurry to build a ceramic shell around the wax tree.

Step 5


Particles of sand are dropped onto the wet tree surface. This help thicken and strengthen the layer of coating on the wet tree surface.

Step 6

Repeat slurry coating and stuccoing

Repeat slurry coating and wax tree stuccoing until the desired shell thickness and strength is reached. Then set and dry wax tree in the dehumidification room.

Step 7


Wax inside the shell is removed by using a steam-dewaxing autoclave.

Step 8


Molten metal is poured into pre-heated mold cavity.

Step 9

Shell Removal

The ceramic shell is removed via hammer knock-out, sand blasting or steel grit blasting.

Step 10

Cut Off

The finished parts are cut free from gatting and runner system.

Step 11

Heat Treatment

Finished parts are heat treated to desired hardness.

Step 12


Remove oxidation layer on the casting surface caused by the casting process. A unified finished surface on the casting helps achieve a high quality result during surface treatment.

Step 13


Using fixture or die straighten finished parts to correct deformation on finished parts.

Step 14

Final Inspection

Castings undergo thorough testing and inspection to ensure that they meet dimension tolerances and specifications.

To start an obligation-free discussion, please direct your initial inquiry to:



5F, No. 189, Sin Hu 3rd Road, Nei Hu District, Taipei 11494, Taiwan
Tel +886-2-8791-7296 | Fax +886-2-8792-1259


Tel +1 949 668 0669