CNC Machinist
Tolerances in this trade are genuinely very small. Working to plus or minus 0.01mm, or tighter, on safety-critical components is not unusual. Understanding what that means in practice, and consistently achieving it, is what defines a skilled machinist. This level of precision requires knowledge, patience, and a systematic approach to every setup and every cut.
What is it?
A CNC (Computer Numerical Control) Machinist is a skilled technician who sets up, programmes, and operates computer-controlled machine tools to cut, shape, and finish metal, plastic, and composite components to precise engineering specifications. CNC machines include lathes, milling machines, grinding machines, and multi-axis machining centres, all controlled by computer programmes that direct cutting tools to produce components with tolerances measured in fractions of a millimetre.
It is a trade that sits at the intersection of practical engineering skill and digital technology. A CNC Machinist needs to understand both the physical reality of cutting metal and the digital logic of the programmes that control the machines. It is one of the most technically demanding and intellectually engaging manufacturing trades, and one that plays a fundamental role in producing the components that make up aircraft, medical devices, automotive parts, defence equipment, and countless other precision-engineered products.
It is also a trade in genuine and sustained demand. UK manufacturing, aerospace, defence, and medical device sectors all depend on skilled CNC machinists, and the combination of retiring experienced machinists and insufficient numbers entering the trade means skilled practitioners are consistently sought after.
What would you actually do?
Depending on your specialism and employer, you could be:
Reading and interpreting engineering drawings and component specifications
Writing or editing CNC programmes using G-code or CAM software
Setting up CNC lathes, mills, and machining centres with correct tooling and fixturing
Loading programmes and carrying out prove-outs on new components
Monitoring machine operation and adjusting cutting parameters for optimal performance
Measuring and inspecting finished components using precision measurement equipment
Identifying and correcting dimensional errors and surface finish problems
Carrying out routine machine maintenance and tool changes
Working to tight tolerances on safety-critical components for aerospace, medical, and defence applications
Operating multi-axis machining centres producing complex three-dimensional components
Collaborating with engineers and quality teams on new component development
Training and mentoring junior machinists as you progress
CNC programming is the natural career progression from machining. Machinists who develop strong programming skills, whether in G-code or CAM software, move into higher-paid, more office-based roles as programmers, process engineers, and manufacturing engineers. The combination of hands-on machining experience and programming knowledge is genuinely powerful.
Career Paths
CNC turning - operating CNC lathes to produce cylindrical components by rotating the workpiece against a cutting tool. Shafts, bushings, pins, and threaded components are typical turned parts.
CNC milling - operating CNC milling machines and machining centres to produce flat, contoured, and three-dimensional components by moving a rotating cutting tool across a stationary workpiece. The most versatile and widely used CNC process.
Multi-axis machining - operating 4-axis, 5-axis, and beyond machining centres capable of producing highly complex components in a single setup. The most technically demanding and best-paid area of CNC machining.
CNC grinding - producing very high precision surface finishes and tight tolerances on hardened components using CNC grinding machines. A specialism in its own right.
CNC programmer - writing and optimising CNC programmes using CAM software such as Mastercam, Fusion 360, or Siemens NX. A more desk-based role that typically follows significant machining experience.
Aerospace machining - working on safety-critical components for aircraft engines, airframes, and systems to the highest quality and traceability standards. A prestigious and well-paid specialism.
Medical device machining - producing implants, surgical instruments, and medical equipment components to exacting standards with full traceability and regulatory compliance.
Toolmaking - producing the jigs, fixtures, moulds, and cutting tools used in manufacturing. A related and highly skilled specialism that overlaps with CNC machining.
Prototype and one-off machining - working in low-volume, high-variety environments producing prototype components and one-off parts for development and research. Requires strong problem-solving and adaptability.
Is it right for you?
You might suit CNC machining if you:
Enjoyed maths, physics, and technology at school and have a practical, logical mind
Are interested in how things are made and fascinated by precision engineering
Like the combination of practical hands-on work and computer-based programming
Take satisfaction in producing something that meets an exact specification
Are methodical and detail-oriented, understanding that a fraction of a millimetre matters
Want a trade that offers genuine career progression from operator to programmer to engineer
Are interested in working in high-technology industries including aerospace, defence, and medical devices
It might not suit you if you need constant physical variety and outdoor work. CNC machining is predominantly factory and workshop-based, often working with the same machines and processes repeatedly.
The skills shortage is real and working in your favour. The UK manufacturing sector faces a well-documented shortage of skilled machinists, particularly those capable of multi-axis work and complex programming. Employers in aerospace, defence, and precision engineering actively compete for good machinists and are generally willing to invest in training and development to retain them.
Skills you will build
Reading and interpreting engineering drawings including geometric dimensioning and tolerancing (GD&T)
CNC programme writing and editing using G-code
CAM software operation, including Mastercam, Fusion 360, or similar
Machine setting, tooling selection, and workholding
Cutting parameter selection, including speeds, feeds, and depths of cut for different materials
Precision measurement using micrometers, verniers, bore gauges, and CMMs (Coordinate Measuring Machines)
Materials knowledge, understanding how different metals, plastics, and composites machine
Quality control and inspection techniques
Machine maintenance and troubleshooting
Understanding of manufacturing tolerances and surface finish requirements
Health and safety in a machine shop environment
How do you get in?
Apprenticeship - a Machining Technician or Precision Engineering apprenticeship at Level 3 is the most structured and well-regarded route. Typically takes three to four years and combines workshop training with college attendance. Many apprenticeships are offered by aerospace, automotive, and precision engineering companies who invest heavily in training because skilled machinists are difficult to recruit.
College course - a Level 2 or Level 3 Diploma in Machining or Mechanical Engineering provides the core technical knowledge and practical skills. Engineering colleges and further education colleges with engineering departments offer these programmes, often with CNC machining as a core component.
T Level in Engineering and Manufacturing - a broader engineering qualification with a substantial industry placement that provides a recognised pathway into precision engineering and machining roles.
Direct entry - some manufacturing companies take on production operatives and train them on specific machines in-house. This tends to produce machine operators rather than fully skilled machinists but can be a valid entry point for those who then invest in additional qualifications and training.
Armed forces route - the Royal Air Force, Royal Navy, and Army all employ engineering technicians working with precision machinery and machine tools. The training is thorough, the qualifications are recognised in civilian employment, and the experience of working on aerospace and defence equipment is genuinely valuable.
Continuous learning is part of the job. CNC technology, CAM software, and manufacturing processes evolve. Machinists who keep their skills current, whether through employer training, self-directed learning, or professional development, remain competitive and employable throughout their careers.
Qualifications to know about
Level 2 Diploma in Machining - the core entry qualification covering manual and CNC machine operation, measurement, and engineering drawing
Level 3 Diploma in Precision Machining - for those progressing to CNC programming, multi-axis work, and more complex components
EAL and City & Guilds Engineering qualifications - widely recognised awarding body qualifications across machining and precision engineering
BTEC Level 3 in Engineering - a broader engineering qualification that includes machining alongside other engineering disciplines
HNC / HND in Mechanical Engineering - higher-level qualifications for those developing towards engineering and technical management roles
Mastercam, Fusion 360, or Siemens NX CAM qualifications - software-specific training and certification increasingly expected by employers in programming roles
ISO 9001 and AS9100 quality system awareness - relevant for those working in aerospace and defence manufacturing where quality management systems are mandatory
COSHH and machine shop safety qualifications - required for working safely with cutting fluids, oils, and hazardous substances in a machine shop environment
What can you earn?
Apprentice: Around £10,000 to £18,000 per year
Qualified CNC machinist: Around £26,000 to £35,000 per year
Experienced machinist: £32,000 to £45,000 per year
CNC programmer or multi-axis specialist: £40,000 to £58,000 per year
Aerospace or defence specialist: £45,000 to £65,000+ per year
CNC machining is one of the better-paying manufacturing trades, reflecting the technical skill and responsibility involved. Aerospace and defence machining commands the strongest rates, particularly for those with security clearance and experience on safety-critical components. Multi-axis programmers and those with CAM software expertise are consistently among the highest earners in the manufacturing sector. Shift allowances and overtime opportunities in production environments add meaningfully to base salary.
What could it lead to?
Senior CNC machinist or cell leader in a precision engineering workshop
CNC programmer writing and optimising programmes for complex components
Multi-axis machining specialist working on the most technically demanding components
Toolmaker producing the precision tooling and fixtures that manufacturing depends on
Quality engineer or inspection technician working with CMMs and measurement systems
Manufacturing engineer or process engineer improving machining processes and efficiency
Production manager or operations manager in a manufacturing environment
CAD and CAM designer combining design and manufacturing knowledge
Your own precision engineering subcontract business
Engineering degree via degree apprenticeship or part-time study for those with strong academic ambition
Tolerances in this trade are genuinely very small. Working to plus or minus 0.01mm, or tighter, on safety-critical components is not unusual. Understanding what that means in practice, and consistently achieving it, is what defines a skilled machinist. This level of precision requires knowledge, patience, and a systematic approach to every setup and every cut.