| Burns Machine Co Milling, Turning, Bending, Welding, Grinding, Assembly · ISO 9001 | Ottawa, IL | MillingTurningBendingWeldingGrindingAssembly | ISO 9001 |
| C & C Machining, Inc Milling, Turning, EDM, Grinding, Finishing | Hayward, CA | MillingTurningEDMGrindingFinishing | - |
| C & S Machine Products Inc Milling, Turning, Swiss, EDM, Grinding · AS9100, NADCAP, ISO 13485 | Niles, MI | MillingTurningSwissEDMGrinding | AS9100, NADCAP, ISO 13485 |
| C + C Mfg Milling, Bending, Welding, Grinding, Finishing | Garden City, ID | MillingBendingWeldingGrindingFinishing | - |
| Caldwell Corp Milling, Turning, Welding, Grinding | Emporium, PA | MillingTurningWeldingGrinding | - |
| Camco Manufacturing Inc Milling, Turning, Grinding, Finishing · ISO 9001, AS9100 | Sayre, PA | MillingTurningGrindingFinishing | ISO 9001, AS9100 |
| Camcraft Inc Milling, Turning, Grinding | Hanover Park, IL | MillingTurningGrinding | - |
| Carlisle Machine Works Inc Milling, Turning, Bending, Welding, EDM, Grinding | Millville, NJ | MillingTurningBendingWeldingEDMGrinding | - |
| Carlson Tool & Manufacturing Corp Milling, Turning, EDM, Grinding | Cedarburg, WI | MillingTurningEDMGrinding | - |
| Cassavant Machining, LLC Milling, Turning, Swiss, Welding, EDM, Grinding, Finishing · ISO 9001, AS9100 | Phoenix, AZ | MillingTurningSwissWeldingEDMGrindingFinishing | ISO 9001, AS9100 |
| Center Tool Co Milling, Turning, Welding, Stamping, EDM, Grinding · ISO 9001 | Hampshire, IL | MillingTurningWeldingStampingEDMGrinding | ISO 9001 |
| Century Tool Co Inc Milling, Turning, Welding, EDM, Grinding | Thompson, CT | MillingTurningWeldingEDMGrinding | - |
| Choice Components Milling, Turning, EDM, Grinding · ISO 9001 | Clinton Township, MI | MillingTurningEDMGrinding | ISO 9001 |
| Clearshot Manufacturing LLC Milling, Swiss, Grinding, Finishing · ISO 9001 | Germantown, WI | MillingSwissGrindingFinishing | ISO 9001 |
| Collins Machine Works Welding, Grinding · CMMC | Portsmouth, VA | WeldingGrinding | CMMC |
| Competitive Engineering, Inc Milling, Turning, EDM, Grinding, Assembly · AS9100 | Tucson, AZ | MillingTurningEDMGrindingAssembly | AS9100 |
| Composite Cutter Technology Inc Grinding · ISO 9001, AS9100 | Wauconda, IL | Grinding | ISO 9001, AS9100 |
| Computer Integrated Machining Inc Milling, Turning, Waterjet, Welding, Stamping, EDM, Grinding, Assembly · ISO 9001, ITAR | Santee, CA | MillingTurningWaterjetWeldingStampingEDMGrindingAssembly | ISO 9001, ITAR |
| Conner Brothers Machine Co., Inc Milling, Turning, Welding, Grinding · ISO 9001 | Bessemer City, NC | MillingTurningWeldingGrinding | ISO 9001 |
| Copen Machine, Inc Milling, Turning, Swiss, Welding, Grinding · ISO 9001 | Kent, OH | MillingTurningSwissWeldingGrinding | ISO 9001 |
| Crater Industries LLC Milling, Turning, EDM, Grinding, Assembly | Santa Clarita, CA | MillingTurningEDMGrindingAssembly | - |
| Creative Machining Systems Inc Milling, Turning, Welding, EDM, Grinding, Finishing | Trenton, NJ | MillingTurningWeldingEDMGrindingFinishing | - |
| Cubitek, Inc Milling, Turning, EDM, Grinding · ISO 9001, AS9100 | Brentwood, NY | MillingTurningEDMGrinding | ISO 9001, AS9100 |
| Custom Machine Milling, Turning, Welding, Grinding | Hagerstown, MD | MillingTurningWeldingGrinding | - |
| Custom Machine & Design Inc Milling, Turning, Waterjet, Welding, EDM, Grinding | Lincoln, NE | MillingTurningWaterjetWeldingEDMGrinding | - |
| Custom Machine Works LLC Milling, Turning, Stamping, Grinding | Fenton, MO | MillingTurningStampingGrinding | - |
| Custom Materials Inc Milling, Welding, Stamping, Grinding, Assembly · ISO 9001 | Chagrin Falls, OH | MillingWeldingStampingGrindingAssembly | ISO 9001 |
| Custom Tool & Model Corp Milling, Turning, Laser, Bending, Welding, Stamping, EDM, Grinding · ISO 9001, AS9100 | Frankfort, NY | MillingTurningLaserBendingWeldingStampingEDMGrinding | ISO 9001, AS9100 |
| Cutco Metal Sawing LLC Milling, Turning, Welding, Grinding | Burleson, TX | MillingTurningWeldingGrinding | - |
| D & D Manufacturing LLC Milling, Turning, Grinding | Ipswich, MA | MillingTurningGrinding | - |
| D.P. Tool Milling, Turning, Welding, EDM, Grinding, Assembly · ISO 9001, AS9100, ITAR | Avon, NY | MillingTurningWeldingEDMGrindingAssembly | ISO 9001, AS9100, ITAR |
| D&F Screw Machine Products Turning, Waterjet, Grinding · ISO 9001 | East Hanover, NJ | TurningWaterjetGrinding | ISO 9001 |
| Dalton Manufacturing Group Inc Milling, Turning, Grinding · ISO 9001, CMMC | Amesbury, MA | MillingTurningGrinding | ISO 9001, CMMC |
| Dearborn Bortec LLC Milling, Turning, Waterjet, Welding, EDM, Grinding, Finishing · ISO 9001, AS9100, ITAR | Fryeburg, ME | MillingTurningWaterjetWeldingEDMGrindingFinishing | ISO 9001, AS9100, ITAR |
| Dearborn, Inc Milling, Grinding | Berea, OH | MillingGrinding | - |
| Decker Machine Works Inc Milling, Turning, Swiss, EDM, Grinding · ISO 9001, AS9100, ITAR | Greenfield, MA | MillingTurningSwissEDMGrinding | ISO 9001, AS9100, ITAR |
| Defelice Engineering, Inc Milling, Turning, Bending, Welding, Casting, Grinding | Mooresville, IN | MillingTurningBendingWeldingCastingGrinding | - |
| Defense & Aerospace Manufacturing LLC Welding, Grinding, Finishing, Assembly | Rancho Cordova, CA | WeldingGrindingFinishingAssembly | - |
| Delco LLC Milling, Turning, Welding, EDM, Grinding · ISO 9001, AS9100 | Akron, OH | MillingTurningWeldingEDMGrinding | ISO 9001, AS9100 |
| Delflo Industries Inc Milling, Turning, Waterjet, Bending, Welding, EDM, Grinding, Assembly · ISO 9001, AS9100, ITAR, ISO 13485, CMMC | Delray Beach, FL | MillingTurningWaterjetBendingWeldingEDMGrindingAssembly | ISO 9001, AS9100, ITAR, ISO 13485, CMMC |
| Delt Forge, Inc Milling, Turning, Welding, Forging, Grinding | Rose City, MI | MillingTurningWeldingForgingGrinding | - |
| Delta Machine Company, LLC Milling, Turning, Welding, Grinding | Harbor City, CA | MillingTurningWeldingGrinding | - |
| Denny Grice Inc Turning, Swiss, Grinding, Finishing | Three Rivers, MI | TurningSwissGrindingFinishing | - |
| Desert Engineering Group Inc Milling, Turning, Stamping, Grinding | Tucson, AZ | MillingTurningStampingGrinding | - |
| Detroit Chrome, Inc Grinding, Finishing · NADCAP | Detroit, MI | GrindingFinishing | NADCAP |
| Deweys Service Company, LLC Laser, Welding, Grinding | Columbia, SC | LaserWeldingGrinding | - |
| Dexter Design & Development Co Milling, Turning, EDM, Grinding, Assembly · ISO 9001 | Hillsboro, OR | MillingTurningEDMGrindingAssembly | ISO 9001 |
| Diamond Die and Mold Milling, EDM, Grinding, Finishing · ISO 9001 | Clinton Township, MI | MillingEDMGrindingFinishing | ISO 9001 |
| Diamond Turning Innovations, LLC Milling, Turning, Grinding | Milford, NH | MillingTurningGrinding | - |
| Dix Metals Milling, Waterjet, Welding, Stamping, Grinding | Huntington Beach, CA | MillingWaterjetWeldingStampingGrinding | - |