Senior Machinist​/Shop Manager

About 9 Mothers

9 Mothers is an Austin-based defense tech company operating as an SOT/Class III manufacturer. Our R&D work spans advanced robotics and novel firearms systems. What you build today will be tested on the range tomorrow.

The Senior Machinist / Shop Manager will be the first and primary machinist on staff. This is a hands‑on production and prototyping role. You will machine parts, maintain equipment, manage consumables and tooling, and serve as the shop authority on design for manufacturability (DFM), actively coaching engineers to improve designs before they reach the floor. As the team grows, this role will take on direct management of junior machinists.

• Establish safety protocols, inventory systems, and maintenance schedules
• Manage consumables, tooling, and fixture inventory on an ongoing basis

• Set up and operate Yama Seiki 5‑axis CNC mill and Yama Seiki CNC lathe to produce prototype and low‑volume production parts from engineering drawings and models
• Write and edit CNC programs (conversational or G-code); optimize feeds, speeds, and toolpaths for prototype iteration cycles
• Perform manual machining operations on mills, lathes, and drill presses as required
• Hold dimensional tolerances consistent with engineering specifications; document inspection results

• Operate polymer and metal additive manufacturing systems; manage post‑processing and finishing across both material classes
• Fabricate fixtures, jigs, and holding devices to support machining and assembly operations

• Review engineering drawings and 3D models prior to manufacture; identify and flag features that are non‑manufacturable, unnecessarily tight, or will drive excessive cycle time
• Work directly with engineers to iterate on designs for manufacturability — communicating tradeoffs clearly and suggesting specific geometric changes
• Provide cycle time and material cost estimates in support of engineering design studies
• Participate in design reviews as the shop authority on machining and fabrication constraints
• Interface with outside vendors and contract manufacturers — communicating specifications clearly, reviewing quotes, and managing delivery of outsourced parts and assemblies

• 10+ years of hands‑on machining experience, including 5‑axis CNC mill and CNC lathe operation and setup
• Demonstrated ability to program CNC equipment (conversational and/or G-code)
• Proficient in creating, optimizing, and proofing multi‑axis toolpaths (including 3+2 and full simultaneous 5‑axis programming) using Mastercam to safely machine complex geometries and prevent machine collisions.
• Proficient in reading and interpreting GD&T engineering drawings and 3D CAD models
• Legally eligible to work with NFA‑regulated items in a licensed manufacturing environment (no disqualifying factors under 18 U.S.C. § 922)
• U.S. citizen or U.S. person as defined under ITAR (22 CFR § 120.62) — required due to the nature of development programs
• Ability to pass an ATF‑required background investigation

• Prior experience in a firearms or defense manufacturing environment
• Experience operating or maintaining polymer and metal additive manufacturing systems
• Familiarity with MIL‑SPEC materials and surface finish requirements
• Prior experience with Yama Seiki CNC lathe and CNC 5‑axis mills
• Prior experience mentoring junior machinists or engineers on DFM
• Exposure to SAAMI or MIL‑STD dimensional requirements for small arms components

Full‑time, on‑site in Austin, TX. This is a startup environment — expect ambiguity, rapid design iterations, and a small team. The shop will be built around this person’s input on equipment and layout. You will interact daily with engineers and be a direct contributor to prototype timelines.

• Meaningful Early Equity:
  You aren't just an employee; you are a foundational owner. Your contributions directly drive the value of your stake in the company.
• Direct Roadmap Influence:
  Forget the bureaucracy of big defense. You will have a seat at the table, directly shaping our product and technology…