| Slagel Manufacturing, Inc Bending, Welding, Finishing · ISO 9001 | Forrest, IL | BendingWeldingFinishing | ISO 9001 |
| Sonic Manufacturing Corporation Milling, Welding, EDM, Grinding, Finishing, Assembly · AS9100, NADCAP | Elk Grove Village, IL | MillingWeldingEDMGrindingFinishingAssembly | AS9100, NADCAP |
| Sugar River Machine Inc Milling, Turning, Welding, Grinding, Finishing, Assembly | South Beloit, IL | MillingTurningWeldingGrindingFinishingAssembly | - |
| Magnetic Inspection Laboratory, Inc Milling, Welding, Finishing · ISO 9001, AS9100, NADCAP, ISO 13485 | Elk Grove Village, IL | MillingWeldingFinishing | ISO 9001, AS9100, NADCAP, ISO 13485 |
| Magnum Steel Works Milling, Turning, Waterjet, Bending, Welding | Mount Vernon, IL | MillingTurningWaterjetBendingWelding | - |
| Acme Industries, Inc Milling, Turning, Welding, Casting · ISO 9001, AS9100 | Elk Grove Village, IL | MillingTurningWeldingCasting | ISO 9001, AS9100 |
| Bland Brothers Enterprises Milling, Welding, Assembly | Springfield, IL | MillingWeldingAssembly | - |
| Sanks Machining Inc Milling, Turning, Waterjet, Welding, EDM, Grinding | Staunton, IL | MillingTurningWaterjetWeldingEDMGrinding | - |
| Tech-Weld Inc Laser, Welding · NADCAP | Sycamore, IL | LaserWelding | NADCAP |
| Wozniak Industries Inc Welding, Stamping, Forging | Schaumburg, IL | WeldingStampingForging | - |
| Helander Metal Spinning Company LLC Milling, Turning, Laser, Waterjet, Welding, Stamping, EDM, Finishing · NADCAP | Lombard, IL | MillingTurningLaserWaterjetWeldingStampingEDMFinishing | NADCAP |
| Wesco Machine & Tool Turning, Laser, Welding, Grinding | Shorewood, IL | TurningLaserWeldingGrinding | - |
| Burns Machine Co Milling, Turning, Bending, Welding, Grinding, Assembly · ISO 9001 | Ottawa, IL | MillingTurningBendingWeldingGrindingAssembly | ISO 9001 |
| Century Metal Spinning Co Milling, Turning, Laser, Bending, Welding, Finishing · ISO 9001, AS9100, ITAR | Bensenville, IL | MillingTurningLaserBendingWeldingFinishing | ISO 9001, AS9100, ITAR |
| Chicago Magnesium Casting Co Welding, Casting · AS9100, NADCAP | Blue Island, IL | WeldingCasting | AS9100, NADCAP |
| Cornell Forge Company Welding, Forging, Finishing, Assembly · ISO 9001, AS9100, NADCAP | Chicago, IL | WeldingForgingFinishingAssembly | ISO 9001, AS9100, NADCAP |
| Kaskaskia Tool and Machine, Inc Milling, Turning, Bending, Welding, Stamping, EDM, Grinding · ISO 9001, AS9100 | New Athens, IL | MillingTurningBendingWeldingStampingEDMGrinding | ISO 9001, AS9100 |
| Machining Systems Corporation Milling, Turning, Welding, Grinding, Finishing · ISO 9001 | Crestwood, IL | MillingTurningWeldingGrindingFinishing | ISO 9001 |
| Target Laser & Machining, Inc Laser, Bending, Welding · ISO 9001 | Rockford, IL | LaserBendingWelding | ISO 9001 |
| H3 Manufacturing Group LLC Laser, Bending, Welding, Finishing · ISO 9001 | Schaumburg, IL | LaserBendingWeldingFinishing | ISO 9001 |
| LJ Fabricators, Inc. Bending, Laser, Welding · ISO 9001 | Rockford, IL | BendingLaserWelding | ISO 9001 |
| Manor Tool & Manufacturing Co Milling, Laser, Waterjet, Bending, Welding, Stamping, EDM, Grinding, Finishing · ISO 9001, ITAR | Schiller Park, IL | MillingLaserWaterjetBendingWeldingStampingEDMGrindingFinishing | ISO 9001, ITAR |
| Midwest Tool Inc. Milling, Bending, Welding | Chicago, IL | MillingBendingWelding | - |
| United Standard Industries Inc Milling, Turning, Welding, Grinding, Finishing · ISO 9001, AS9100 | Glenview, IL | MillingTurningWeldingGrindingFinishing | ISO 9001, AS9100 |
| Accurate Metals Illinois Laser, Welding · ISO 9001 | Rockford, IL | LaserWelding | ISO 9001 |
| Chicago Metal Fabricators Bending, Laser, Welding · ISO 9001, ITAR | Chicago, IL | BendingLaserWelding | ISO 9001, ITAR |
| Evergreen Machining Services Milling, Welding, Stamping, Metal AM · ISO 9001 | Rockford, IL | MillingWeldingStampingMetal AM | ISO 9001 |
| NKP Metals LLC Waterjet, Welding | Chicago, IL | WaterjetWelding | - |
| Saporito Finishing Co Welding, Finishing · NADCAP | Cicero, IL | WeldingFinishing | NADCAP |
| The Bennu Group Inc Milling, Turning, Waterjet, Welding, Finishing · ISO 9001 | South Holland, IL | MillingTurningWaterjetWeldingFinishing | ISO 9001 |
| 360 Machine Shop Milling, Turning, Laser, Welding, Metal AM | Bloomington, IL | MillingTurningLaserWeldingMetal AM | - |
| Astoria Wire Products Inc Milling, Laser, Punching, Bending, Welding | Bedford Park, IL | MillingLaserPunchingBendingWelding | - |
| Atlas Tool & Die Works Inc Turning, Laser, Waterjet, Welding, Stamping, EDM, Assembly | Lyons, IL | TurningLaserWaterjetWeldingStampingEDMAssembly | - |
| Bennett Metal Products Inc Milling, Turning, Waterjet, Welding · ISO 9001, ITAR | Mount Vernon, IL | MillingTurningWaterjetWelding | ISO 9001, ITAR |
| CM Fabrication, LLC Milling, Laser, Welding, Finishing | Sycamore, IL | MillingLaserWeldingFinishing | - |
| Custom Laser Works LLC Laser, Bending, Welding | Addison, IL | LaserBendingWelding | - |
| Foster Works LLC Laser, Punching, Bending, Welding, Stamping, Finishing | Chicago, IL | LaserPunchingBendingWeldingStampingFinishing | - |
| Jacksonville Machine, Inc Milling, Turning, Welding, Grinding · ISO 9001 | Jacksonville, IL | MillingTurningWeldingGrinding | ISO 9001 |
| Kocsis Brothers Machine Company Welding, Assembly | Alsip, IL | WeldingAssembly | - |
| Laystrom Manufacturing Company Bending, Laser, Welding | Chicago, IL | BendingLaserWelding | - |
| Morgan Bronze Products, Inc Turning, Welding, Casting · ISO 9001 | Lake Zurich, IL | TurningWeldingCasting | ISO 9001 |
| Surface Finishes Welding, Grinding · ITAR | Addison, IL | WeldingGrinding | ITAR |
| Aztec Plastic Company Welding, Stamping, Grinding, Finishing, Assembly | Chicago, IL | WeldingStampingGrindingFinishingAssembly | - |
| B T M Industries Inc Milling, Turning, Welding, Casting, Grinding | Woodstock, IL | MillingTurningWeldingCastingGrinding | - |
| Chicago Metal Supply & Fabrication Inc Bending, Welding, Waterjet, Stamping | Chicago, IL | BendingWeldingWaterjetStamping | - |
| Odin Fabrication, Inc Laser, Punching, Welding, Finishing | Elburn, IL | LaserPunchingWeldingFinishing | - |
| Chicago Fabrications Turning, Bending, Welding | Chicago, IL | TurningBendingWelding | - |
| Comet Fabricating & Welding Co Laser, Bending, Welding | Rockford, IL | LaserBendingWelding | - |
| Ki Machine Tools & Productions Inc Milling, Turning, Bending, Welding, EDM, Grinding | Loves Park, IL | MillingTurningBendingWeldingEDMGrinding | - |
| Mennie's Machine Co Milling, Turning, Welding, Grinding · IATF 16949 | Mark, IL | MillingTurningWeldingGrinding | IATF 16949 |