Senior Machinist / Shop Manager

Location: Onsite — Austin, TX

Employment Type: Full‑Time

Job Title: 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. This is a ground-floor role — you will help spec, source, and stand up the machine shop from scratch, then run it. What you build today will be tested on the range tomorrow.

Position Summary

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.

Essential Duties

Shop Buildout & Operations

• Collaborate with engineering and operations leadership to specify, procure, and install machine shop equipment for a new R&D facility

• Establish shop layout, safety protocols, inventory systems, and maintenance schedules

• Manage consumables, tooling, and fixture inventory on an ongoing basis

CNC & Manual Machining

• Set up and operate 5-axis CNC mills and CNC lathes 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

Fabrication & Additive Manufacturing

• Perform sheet metal layout, cutting, forming, and finishing operations

• 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

NFA / Firearms Compliance

• Manufacture, handle, and mark NFA items (suppressors, machine guns, destructive devices) in compliance with ATF regulations applicable to an SOT/Class III manufacturer

• Maintain accurate records required under 27 CFR Part 478/479 for all regulated items produced in the shop

• Coordinate with the Responsible Person / RO on any ATF-required approvals prior to fabrication of NFA items

Engineering Collaboration & DFM

• 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

Requirements

• 10+ years of hands-on machining experience, including CNC mill and CNC lathe operation and setup

• Demonstrated ability to program CNC equipment (conversational and/or G-code)

• Proficient in reading and interpreting GD&T engineering drawings and 3D CAD models

• Experience with sheet metal fabrication

• 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

Nice‑to‑Have

• 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

• Experience standing up or significantly expanding a machine shop

• Prior experience mentoring junior machinists or engineers on DFM

• Exposure to SAAMI or MIL-STD dimensional requirements for small arms components

• Experience with MIG or TIG welding

Work Environment

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.

Benefits

• 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 trajectory from day one.

• Mission-Critical Work: We don't build for "what if." We build systems the Department of War actively needs to counter immediate, real-world threats.

• The Builder's Playground: Work in a brand-new lab fully optimized for rapid prototyping, equipped with NVIDIA Jetsons, high-end scopes, and 3-D printers.

• 100% Employer-Paid Premiums: We cover 100% of your medical, dental, and vision insurance premiums and cover 50% of healthcare premiums for your dependents.

• Unlimited PTO: We value results, not clock-watching. Take the time you need to stay sharp and recharge.

• Zero Red Tape: You report to the founders. You have the autonomy to make technical decisions that would take months of committee approval at a larger firm.

• Austin-Based Culture: Join an onsite team in Austin, TX, where we prioritize high-bandwidth collaboration and rapid field-testing.

• Relocation Assistance: We want the best talent in the room. If you aren't in Austin yet, we’ll help you get here, to make your transition to the Silicon Hills seamless.

About the Interview

1. Application screen phone call (30 min)

2. Virtual interview with Director of Operations (30 min)

3. Virtual interview with Director of Mechatronics and Director of Mechanical Engineering (45 min via MS Teams)

4. Virtual interview with co-founder/COO (15 min via MS Teams)

5. In-person visit to Austin

6. Offer