| Professional Metal Works Bending, Laser, Welding · ISO 9001 | Lansing, MI | BendingLaserWelding | ISO 9001 |
| Robmar Precision, Inc Milling, Turning · ISO 9001, ITAR | Westland, MI | MillingTurning | ISO 9001, ITAR |
| Rocktech Milling, Grinding | Chesterfield, MI | MillingGrinding | - |
| S & S Die Co Milling, Turning, Welding, EDM, Grinding | Lansing, MI | MillingTurningWeldingEDMGrinding | - |
| Schaefer Screw Products Co Milling, Turning, Grinding, Finishing | Garden City, MI | MillingTurningGrindingFinishing | - |
| Sigma Machine Inc. Milling, EDM | Kalamazoo, MI | MillingEDM | - |
| Smith Metal, LLC Milling, Turning, Swiss, Laser, Waterjet, Bending, Welding, EDM, Grinding, Finishing · ISO 9001 | Augusta, MI | MillingTurningSwissLaserWaterjetBendingWeldingEDMGrindingFinishing | ISO 9001 |
| Spearpoint Manufacturing LLC Milling · ISO 9001, ITAR, CMMC | Traverse City, MI | Milling | ISO 9001, ITAR, CMMC |
| Streamline Machine Source Inc Milling, Laser, Waterjet, Grinding · ISO 9001 | Greenville, MI | MillingLaserWaterjetGrinding | ISO 9001 |
| Sturdy Grinding & Machining Inc Grinding, Finishing · ISO 9001 | New Haven, MI | GrindingFinishing | ISO 9001 |
| Supreme Gear Co Milling, Turning, Grinding · ISO 9001, NADCAP | Fraser, MI | MillingTurningGrinding | ISO 9001, NADCAP |
| Taylor Turning Inc Milling, Turning, Grinding | Wixom, MI | MillingTurningGrinding | - |
| TMD Machining Inc Milling, Turning, Swiss, EDM, Grinding · AS9100, NADCAP | Plainwell, MI | MillingTurningSwissEDMGrinding | AS9100, NADCAP |
| Tompkins Products, Inc Milling, Welding, Grinding, Finishing · IATF 16949 | Detroit, MI | MillingWeldingGrindingFinishing | IATF 16949 |
| Trutron LLC Milling, Turning, EDM, Grinding | Troy, MI | MillingTurningEDMGrinding | - |
| U. P. Machine & Engineering Co Turning | Powers, MI | Turning | - |
| United CNC Machining Milling, Turning, Laser, Waterjet, Welding, EDM, Grinding, Finishing · ISO 9001, AS9100, ITAR, NADCAP, CMMC | Auburn Hills, MI | MillingTurningLaserWaterjetWeldingEDMGrindingFinishing | ISO 9001, AS9100, ITAR, NADCAP, CMMC |
| Valley City Metal Products Milling, Turning, Laser, Stamping · ISO 9001 | Shelby, MI | MillingTurningLaserStamping | ISO 9001 |
| W. G. Benjey, Inc Milling, Turning, Welding, Finishing | Alpena, MI | MillingTurningWeldingFinishing | - |
| Warner Bros, Foundry Co Welding, Casting | Roseville, MI | WeldingCasting | - |