Job descriptions for CNC and precision machining shops: define the skill, not just the task

Open the job description file in most machine shops and you will find something like this. 'Operate CNC machine as per drawing. Maintain quality. Follow safety rules. Keep the area clean.' It describes a helper who loads blanks and a setter who proves new programs equally well. So the hiring advert draws both, and pay gets argued from the title.

The machining group overview puts role design early for a reason. In a shop with a thin skill ladder, the description is where the ladder gets written down.

• They name activities, not ability. 'Operate machine' says nothing about whether the person can touch an offset.
• They ignore the controller. Someone fluent on one control may be lost on another, and the description never says which.
• They skip decisions. The costly mistakes happen when someone decides alone what they should have escalated, or the reverse.
• They give no evidence. There is no way to tell whether a person meets the description, so it plays no part in hiring or pay.
• They never change. The card written when the shop had three lathes still sits in the file after five machining centres arrived.

• Purpose of the role in one sentence.
• Machine families and controllers the person is cleared on.
• Work done unassisted, written as observable tasks: picks up a datum with an edge finder, sets tool nose radius compensation, edits a canned cycle or a subprogram, bores soft jaws to suit a casting.
• Decision rights and their limits: what they may change, stop, release or must escalate.
• Handovers: what they pass to the next shift, the inspector or the programmer.
• Evidence: how each skill is checked, and by whom.
• Next grade: the extra tasks needed to move up.

Purpose: gets each job on the VMCs to a good first-off and keeps it there across the shift.
Machines and controllers: the shop's vertical machining centres, on the controllers listed on the skill grid.
Unassisted work: loads and clocks fixtures, sets work offsets by probe or edge finder, measures tool lengths, runs new programs in single block with reduced rapids.
Decision rights: may edit feeds, speeds and wear offsets on a proven program; may stop any run he doubts; may not change a toolpath without the programmer.
Release: approves first-offs on repeat parts; holds first-offs on new parts for the inspector.
Handover: fills the setup sheet and the shift note for every job he touches.
Teaching: brings one named operator up through the setter tasks on the grid.
Evidence: each task signed off by the production head after watching it done alone.
Next grade: proves new parts on costly castings and covers the senior setter's machines.

1. 1

   Shadow your strongest jobholder for a shift

   Note what they actually do, hour by hour, including the things they handle without being asked.

2. 2

   List decisions before chores

   Ask what they decide alone, what they escalate and what they wish they could decide. Decisions shape the role more than cleaning duties do.

3. 3

   Write limits in plain words

   'May adjust a wear offset within the limit on the check plan. Beyond it, stop and call the setter.' Limits stop both timid and reckless behaviour.

4. 4

   Define the evidence

   For each task, say who checks it and how. A task with no check is a hope, not a requirement.

5. 5

   Connect the card to a grade

   Each card sits on one rung of the grade ladder, with the next rung's tasks listed at the bottom.

6. 6

   Read it back to the people in the role

   Two or three jobholders will catch gaps or wishful items within minutes.

7. 7

   Revisit when the shop changes

   A new machine, a new controller or a new kind of customer part means the cards need a look.

• Loader and deburring helper: loads blanks, deburrs cross-holes with a hand scraper, washes and oils parts, and starts on the first operator tasks.
• Operator, with separate machine sections: on turning, changing an insert or collet; on milling, swapping vice jaws and parallels.
• Setter, split by section: on milling, clocking fixtures and picking up datums by probe; on turning, boring soft jaws and aligning the tailstock.
• CAM programmer: builds stock and fixture models, sets stepover and scallop height, runs gouge checks and simulation, edits the post-processor and takes feedback from the floor.
• Inspector: works the height gauge, sine bar and slip gauges, the profile projector and the roughness tester, holds release authority and traces complaints.
• Tool crib and presetter staff: assemble holders, measure lengths on the presetter, track insert stock and send cutters for regrinding.
• Night lead, whose decision rights matter most when nobody senior is awake.

Use the same card for the job advert, the practical test, induction, the skill grid, the yearly review. This is what role design work aims for: one document that every people decision draws on. For close-tolerance repeat work, see the component makers role design page. One-off builds need versatile all-rounders, which the jig and fixture role design page addresses. When the cards are ready, our guide to hiring and testing skilled machinists shows how to use them at the hiring bench.