| Craftco Metals Services Inc Milling, Turning, Laser, Waterjet, Bending, Welding, Finishing, Assembly | Sheridan, WY | MillingTurningLaserWaterjetBendingWeldingFinishingAssembly | - |
| Criterion Manufacturing Turning, Welding | Waterloo, IA | TurningWelding | - |
| Crown Machine Inc Milling, Turning, Welding, EDM · ISO 9001 | Rockford, IL | MillingTurningWeldingEDM | ISO 9001 |
| CS Tool Engineering, Inc Milling, Welding | Cedar Springs, MI | MillingWelding | - |
| Cumberland Machine Co Milling, Turning, Welding | Nashville, TN | MillingTurningWelding | - |
| Custom Aerospace Milling, Turning, Welding, EDM, Finishing, Assembly | Palm Bay, FL | MillingTurningWeldingEDMFinishingAssembly | - |
| Custom Manufacturing & Polishing Inc Waterjet, Welding | Springfield, MO | WaterjetWelding | - |
| Custom Manufacturing Co Bending, Laser, Welding, Stamping · ISO 9001 | Dallas, TX | BendingLaserWeldingStamping | ISO 9001 |
| Custom Metalcraft Milling, Bending, Welding | Springfield, MO | MillingBendingWelding | - |
| Custom Welding by Law, Inc Waterjet, Bending, Welding | Orlando, FL | WaterjetBendingWelding | - |
| Cut- Out Creations Milling, Turning, Welding | Rochester, NY | MillingTurningWelding | - |
| Cutco Metal Sawing LLC Milling, Turning, Welding, Grinding | Burleson, TX | MillingTurningWeldingGrinding | - |
| Cutting Edge Fabrication Inc Milling, Bending, Laser, Welding · ISO 9001 | Milwaukee, WI | MillingBendingLaserWelding | ISO 9001 |
| Cutting Edge Manufacturing Milling, Bending, Welding · ISO 9001, AS9100 | Caldwell, ID | MillingBendingWelding | ISO 9001, AS9100 |
| Cutting Edge Solutions Mfg & Mro LLC Welding | Yuma, AZ | Welding | - |
| Cutting Solutions Turning, Laser, Waterjet, Bending, Welding, Grinding, Finishing, Assembly | Zeeland, MI | TurningLaserWaterjetBendingWeldingGrindingFinishingAssembly | - |
| CV International, Inc Milling, Turning, Laser, Punching, Bending, Welding · ISO 9001 | Bend, OR | MillingTurningLaserPunchingBendingWelding | ISO 9001 |
| Cyclefab, LLC Milling, Turning, Welding | Renton, WA | MillingTurningWelding | - |
| D & D Automation Inc Milling, Turning, Welding, EDM | Terre Haute, IN | MillingTurningWeldingEDM | - |
| D & G Manufacturing LLC Milling, Turning, Welding | Aurora, CO | MillingTurningWelding | - |
| D. J. Fabricators, Inc Milling, Laser, Waterjet, Punching, Bending, Welding, EDM, Grinding, Assembly · ISO 9001 | Ipswich, MA | MillingLaserWaterjetPunchingBendingWeldingEDMGrindingAssembly | ISO 9001 |
| Dahlgren Technologies LLC Welding | King George, VA | Welding | - |
| Dallas Fabrication Welding | Carrollton, TX | Welding | - |
| Dallas Machine and Tool Milling, Welding | Carrollton, TX | MillingWelding | - |
| Dallas Metal Fabricators Inc. Laser, Welding | Dallas, TX | LaserWelding | - |
| Davis Industries Milling, Turning, Punching, Bending, Welding, Assembly · ISO 9001, AS9100 | Phoenix, AZ | MillingTurningPunchingBendingWeldingAssembly | ISO 9001, AS9100 |
| Davis Tool & Die, Inc Milling, Turning, Welding, Stamping, EDM, Grinding | Abbeville, MS | MillingTurningWeldingStampingEDMGrinding | - |
| Davlan Engineering Inc Milling, Turning, Laser, Welding, Stamping | Saint Louis, MO | MillingTurningLaserWeldingStamping | - |
| Dawid Manufacturing Inc Milling, Welding | Ansonia, CT | MillingWelding | - |
| DGF Industrial Innovations Group, Ltd Milling, Turning, Bending, Welding · ISO 9001 | Gilford, NH | MillingTurningBendingWelding | ISO 9001 |
| Diamond W Custom Machine Works LLC Milling, Turning, Laser, Waterjet, Welding, Finishing | Phillipsburg, KS | MillingTurningLaserWaterjetWeldingFinishing | - |
| Dicostanzo Welding Services LLC Welding | Anderson, SC | Welding | - |
| Digital Machining Systems LLC Milling, Turning, Welding, Assembly · ISO 9001 | Duson, LA | MillingTurningWeldingAssembly | ISO 9001 |
| Distinctive Machining LLC Milling, Welding, Grinding, Finishing | Zeeland, MI | MillingWeldingGrindingFinishing | - |
| Diversified Machining Inc Milling, Welding | Forest Hill, MD | MillingWelding | - |
| DK Machining LLC Milling, Turning, Welding, Assembly · ISO 9001, ITAR | Molalla, OR | MillingTurningWeldingAssembly | ISO 9001, ITAR |
| Dms-South/bailey Tool LLC Milling, Turning, Welding, Stamping, EDM | Lancaster, TX | MillingTurningWeldingStampingEDM | - |
| Donsco, Inc Milling, Welding, Casting | Wrightsville, PA | MillingWeldingCasting | - |
| Douglas Machine & Engineering Milling, Turning, Bending, Welding, EDM · ISO 9001, AS9100, ITAR, CMMC | Davenport, IA | MillingTurningBendingWeldingEDM | ISO 9001, AS9100, ITAR, CMMC |
| Draeving Machine Tool, Inc Milling, Turning, Welding, EDM | Beloit, WI | MillingTurningWeldingEDM | - |
| Drews Fabrication and Welding LLC Welding | Longview, WA | Welding | - |
| DRM Industries Corp Milling, Turning, Laser, Welding, Casting · ISO 9001 | Lake Delton, WI | MillingTurningLaserWeldingCasting | ISO 9001 |
| Dual Machine Milling, Turning, Welding · ISO 9001, AS9100 | Indianapolis, IN | MillingTurningWelding | ISO 9001, AS9100 |
| Dualtron Manufacturing Milling, Laser, Punching, Welding, Finishing, Assembly | West Babylon, NY | MillingLaserPunchingWeldingFinishingAssembly | - |
| Dupage Machine Products, Inc Welding, EDM | Bloomingdale, IL | WeldingEDM | - |
| DW Engineering LLC Milling, Turning, Welding | Burnsville, MN | MillingTurningWelding | - |
| DW Products Milling, Turning, Bending, Welding, Waterjet · ISO 9001, ITAR | Cedar Rapids, IA | MillingTurningBendingWeldingWaterjet | ISO 9001, ITAR |
| Dynamic Metals LLC Milling, Laser, Bending, Welding, Stamping · AS9100, NADCAP | Elkhart, IN | MillingLaserBendingWeldingStamping | AS9100, NADCAP |
| Dynamic Sheetmetal Fabrication, LLC Bending, Welding · ISO 9001 | St Paul, MN | BendingWelding | ISO 9001 |
| Dynamix Manufacturing LLC Milling, Turning, Welding | Joplin, MO | MillingTurningWelding | - |