An extensive range of robust fittings and weatherproof products.


Connectivity solutions such as high brackets, busbars, and connector pins.

Power Transmission & Distribution

Connectors & structural components for cutouts, transformers, & substations.


Complex sensor housings & fracture-critical products.


Robust castings and assemblies for everyday appliances.

Commercial Hardware

Finished components for commercial & residential hardware applications.

Electronics & Telecom

Precision metal stamped sensors, connectors and cast housings & covers.

Fluid Power

Durable, precision products for high-pressure applications.

Food & Beverage

Handles, leveling pins, flow valves & button housings.


Custom housings to fully assembled commercial & industrial light fixtures.


Durable corrosion-resistant engineered castings and subassemblies.

Medical & Dental

Medical-grade parts for implants, housings, manifolds, and pumps.

Oil & Gas

Custom housings and covers for flow control, pressure valves & meters.

Power Tools

Durable yet lightweight custom metal housings.


Innovative precision metal stamped parts.

High Pressure Die Casting

High-pressure liquid metal is pressed into a precision metal mold cavity, and then cooled & solidified under pressure.

Ideal for a wide range of applications, including automotive, agricultural, electronics, and medical.

Sand Casting

Castings with complex shapes & inner cavities that are produced in a sand mold

Ideal for parts with complex shapes and inner cavities

Gravity Die Casting

A mold is filled with liquid metal using gravity and cooled and solidified in the mold to obtain a casting

Ideal for parts with complex shapes made with steel, aluminum or magnesium alloys

Investment Casting

A process used to obtain a mold without a parting surface; creates parts with high dimensional & geometric accuracy

Ideal for near-net shaped parts with complex shapes and high precision requirements

Partner Services

Custom Tooling, Machining, Surface Finishing, Special Purpose Machine Design & Development

Precision Metal Stamping

More than 80 presses convert metal sheets into custom parts

Ideal for parts for electronic connectors and microprocessor chips

Swiss Screw Machining

A specialized CNC machine capable of producing extremely small, precise parts

Ideal for complex miniature screws, contact pins & micro-fasteners

Partner Services

Rapid Prototypes, Heat Treating, Automated Assembly

Company History

Learn more about our company milestones.

Plant Locations

Learn more about our global manufacturing facilities.

Company News

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Contact Us

Let us know how we can help create a solution for you


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Global Code of Conduct

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Innovation at Sigma

Purposeful innovation – the continual improvement and innovation of custom-designed and precision-made products and solutions.

Engineered Solutions

Sigma offers solutions for complex product characteristics and technical requirements.

Global Supply Chain Management

U.S.-based supply chain management teams support our customers.

Partner Services

Sigma is a vertically integrated single-source solution provider.

Investment Casting

Investment casting is based on one of the oldest known metal-forming techniques and produces near-net-shape precision parts that usually require few finishing details.

Investment Casting Process

  • Step 1: Wax is injected into a die to produce a pattern
  • Step 2: Patterns are affixed to a wax runner bar to create an assembly called a ‘tree’
  • Step 3: A tree is dipped into a slurry to build up a ceramic shell
  • Step 4: The wax is melted out of the shell using heat and pressure
  • Step 5: The dewaxed ceramic shell is fired at 2000 degrees in a kiln
  • Step 6: Metal is poured into the fired shell
  • Step 7: The ceramic shell is knocked off the casting


factory working working with investment casting die

Investment Casting Capabilities

Sigma works with more than 200 alloys, including stainless steel, carbon steel, aluminum, brass, bronze, copper, nickel, and high-temperature alloys.

metal parts that were investment cast

Investment Casting Applications

Part sizes typically range from 1 ounce to as much as 100 pounds and can be found in tough industrial applications such as power generation, oil & gas, fluid power, medical and dental, and aerospace and aviation.


Investment casting creates precision products with high dimensional and geometric accuracy. Because near net-shape parts are created, investment casting saves time and money by reducing the need for secondary operations. Investment casting provides many advantages - it can achieve tighter dimensional tolerances compared to sand casting; shorter lead times; greater precision and accuracy compared to metal fabrication; and lower tooling costs versus forging.