Sand Castings

Production Metal Casting Process

Sand Mold Casting Parts

Sand Casting is the process of making cast metal parts using sand molds. This metal casting process utilizes two “match plates” that are used to form the sand (mixed with a “binder”) into the desired shape. The sand mold halves become the “die” used in the casting process. Molten metal is poured into the sand “die” to form the metal castings.

Sand Mold Casting
Sand Mold casting

Sand for Metal Casting  

Air set sands are a great choice for sand mold castings. Silica sand (SiO2) is the most typical type of metal casting sand.  This is mixed with a binder to create a mold. Using sand as the mold material offers several benefits to the casting process.

Metal Casting Sand

Benefits of Fine-Grain Air Set Sand Castings

At Precise Cast, we pride ourselves on our quality sand castings. Because of our unique sand process, we are able to obtain smooth surface finishes of Ra 120-220.

With Fine-grain air set castings large, thick, and/or heavy parts can be successfully cast. We are capable of casting parts with thick cross-sectional areas and a typical wall thickness of .150”-.500”.

Sand Castings provide excellent mechanical properties and parts requiring cores are easily done. Simple and very complex parts are achievable and prototype to low-volume-production quantities is possible.

Typical first article lead time is 1-2 weeks (expedited lead times are available)

Prototype to low-volume-production quantities is possible.

Our “air set” process yields a surface finish much smoother than any other sand casting process resulting in Ra 120-220 finish. 

Sand mold castings
sand mold casting

Cost-effective Metal Castings

Besides the other great benefits of Sand casting, it is the least expensive casting process, especially when producing small quantities of parts.


Cost-effective manufacturing/prototyping solution for quantities of 5-2,000 EAU.

Cost-effective for larger part geometries (usually less costly than plaster casting for parts over 14” in any axis).

Better than Permanent Mold or Die Cast Tooling?

although all options have their benefits there is a significant difference when deciding to pursue sand castings. The tooling process is much quicker than permanent mold or die casting tooling processes. also, tooling costs are lower than permanent mold and die casting tools. Helping you save time and money on your project. Talk to our experts for your next metal casing part quotes and get more benefits with sand mold castings.

Metals | Alloys 

Aluminum  Magnesium | Zinc

At Precise Cast, we specialize in aluminum, zinc, and magnesium metal castings. We use two preferred methods to produce your parts; sand mold casting and plaster mold metal casting.  When it comes to your sand mold castings, let our engineering team work directly with your product designers to find the best metal for your project. Learn more about each metal below. 




Added Value Services

Learn more about our capabilities and additional services for all your rapid prototyping and low-volume manufacturing needs.

Prototype Castings

One-off or low-volume castings in magnesium, zinc, and aluminum. 

Quality Inspecting/ Testing

Dedicated quality inspection with every part

CNC Machining

3-, 4- 5- axis machines. We machine our metal castings too!

Sand Casting Process


1) Master Pattern Design: 

Precise Cast converts 3-D CAD data into a master pattern. Gating (rigging) and shrink compensation are factored into the CAD during this tooling design phase. Depending on part geometry, FEA solidification analysis is run to optimize the tooling design.

2) Match Plates/Tooling: 

A 3-D solid model is used to machine a match plate.

3) Forming the Mold:

Sand is mixed with the proper chemicals for binding. A compaction table is used to ensure optimal compaction. The sand mixture is metered into the match plates where it is left to harden. The mold halves (cope and drag) are then removed from the match plates and assembled for metal pouring.

4) Pouring the Metal: 

A gravity pour method of filling the cavity is used. Variables that affect casting quality are carefully controlled. These variables include metal temperature, mold temperature, cooling rate, mold tilt, riser size and location, and metal filtering. We use rotary degassing, a continuous melt furnace, and employ a reduced atmospheric testing system to ensure optimal results. Each mold and corresponding part is serialized.

5) Break Out: 

After the metal has solidified, the sand is carefully broken away to reveal the metal casting.

6) Parts Cleaning:

Next comes the removal of gates, chills, runners, and minor casting imperfections. The result is a “raw” casting.

7) Machining: 

Final machining is often used to create high-tolerance geometries that are either beyond the capabilities or not economical to incorporate into the casting process. We have a machining department dedicated to the machining of castings. Our technology includes multi-axis capability and probe technology to ensure consistent and accurate machining of each casting.

Why Precise Cast?

We built our company from the ground up with one thing in mind- our customer. This meant being the leaders in efficiency, innovators in manufacturing, and masters of our craft. Providing you with exceptional service and forward-thinking manufacturing options. We strive to be the best in metal casting and machining.

Free and Easy Consultations 

Have questions? ALL CONSULTATIONS ARE FREE! We also offer secure file uploading so you can quickly send over any preliminary or finished items for us to review. We are happy to discuss any concerns and questions you have about the casting process. Our team is dedicated to proving exceptional customer service and an in-depth analysis of your project.

Get started on your next project and see why we are the #1 choice in  Custom Rapid Prototyping and Low Volume Manufacturing.

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