How to Produce Complex Castings with Extreme Precision using the Lost-Wax Method

What is Lost Wax Casting?

A component made by lost wax casting, also known as investment casting, typically features tighter tolerances, thinner walls, and a superior surface polish compared to a component made by sand casting. The Lost Wax method differs from other casting methods because of the way the mold is made.

This process involves casting a single piece using the wax model or pattern or casting multiple pieces based upon a wax “casting tree” (or gating system). A thick coating of ceramic coating forms around a wax model or casting tree after it is repeatedly dipped into a ceramic slurry and then into ceramic powder. Once the ceramic mold has been cured and reached the required hardness, it becomes the lost wax casting mold. The ceramic mold is then filled with molten metal, the wax melts away as the metal cools, and the ceramic mold can be removed to reveal the cast metal part.

Lox Wax Method for Simple & Complex Shapes

Components that are complex-shaped can be made using the lost wax casting for a number of reasons:

1. Features of undercutting

For components that require complex internal shapes, investment casting is the ideal process. For undercut details, removable inserts are perfect, and ceramic preformed cores and soluble wax cores can also be used when removable inserts are not available.

2. Internal Corners

When internal corners of lost wax casts are formed with the largest fillet radii possible, stress can be raised. A casting produced through the lost wax method will not have sharp edges or burrs like a casting produced through machined cornering.

3. Datum Planes

Rather than locating datum plans at one end of the casting, datum plans are placed across the center of it to satisfy the functional requirements of the component.

4. Surface finishing with exceptional quality

In comparison to other casting methods, lost wax casting produces a higher surface polish. The precise tolerances, less or no machining, and superior surface polish of the casting make the tolerances tighter than those of other casting methods. A product can be enhanced by casting elaborate writing or a logo on its surface, although polishing is not always necessary. This is something that can be addressed in the casting design phase, although the amount of machining required will completely depend on the specifications of our clients.

5. Quality Consistency

Since the wax pattern will be an exact reproduction of the metal component when cast, lost wax casting is often used when design consistency is required. This is especially advantageous when it comes to parts that can be utilized in a variety of industries and applications. You must specify the dimensions, geometries, and complexity of the metal component, regardless of whether you are producing small or large quantities. The dimensional accuracy of casted molds and metal products can be maintained through the lox wax method.

6. Production Consistency & Reproducibility

In addition to their ability to be easily modified when design changes are required, these dies are also extremely durable, it has the advantage of being repeatable since a given amount of pieces can be produced consistently when it comes to production runs of high volume.

7. A closer net shape and tighter tolerances

Lost wax casting is also known as investment or precision casting, especially for stainless steel castings. In comparison to similar manufacturing procedures, CIREX can meet good tolerance levels according to the international norm VDG P690 D1, which reduces the need for extra machining. During casting, we leave a small allowance for machining, meaning subsequent machining will be minimal, even if stricter tolerances are required. Due to this, we can produce items that are net or nearly net shaped. There may be situations in which other casting methods cannot accommodate this.

8. Less Casting Defects

Compared to sand casting, the lost wax method produces high-quality goods with fewer casting defects, and our rejection rate is much lower than that of sand casting. We, however, do not eliminate the possibility of defects occurring, which is why, following the completion of production, an inspection is conducted to ensure there are no defects left in the products and to ensure that our customers receive products free of defects.

CIREX your Lost Wax Casting Specialist

CIREX is one of the world’s largest lost wax foundries. Lost wax castings with complex shapes and high dimensional accuracy can be produced by the lost wax method. In addition, this method allows for a great deal of freedom in material selection and design. Castings can be customized to meet specific requirements, including those for medical, aerospace, energy, industrial automation, automotive applications, and more. Having decades of experience using the lost wax method, we can assure you that the casts that we produce are of the highest quality. Contact us for more information now.