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WI-120 Machine Startup and First-Piece Approval

WI-120 Machine Startup and First-Piece Approval

Revision E · Effective 2025-08-11

1 Purpose

This instruction defines how CNC machines are started up at the beginning of a shift or job, how the first piece of a setup is approved, and how in-process checks are performed so that nonconforming parts are caught before a production run continues.

2 Scope

Applies to all CNC mills, lathes and 5-axis/horizontal machining centers at the Wichita plant, including Bay 2 grinding and Bay 5 machining. It covers every job, with mandatory inspector verification before any production on flight hardware. First Article Inspection (FAI) to AS9102 is a separate requirement covered by QP-8.6 and WI-210; a first-piece approval does not replace an FAI.

3 Definitions

  • Warm-up program: the 10-minute spindle and axis warm-up program WU-10, stored in the control of every CNC machine.
  • First piece: the first part produced after a new setup, a program edit, a tool change that affects a characteristic, or a machine crash.
  • Control plan: the job-specific inspection plan attached to the traveler, listing characteristics, gages and check frequency.
  • Flight hardware: any part the traveler or PO identifies as installed on an aircraft, spacecraft or missile.

4 Responsibilities

  • Operator: runs the warm-up, measures the first piece, records results on the traveler, performs in-process checks.
  • Quality inspector: verifies the first piece and stamps the traveler with an issued inspection stamp (WI-410, F-410-03).
  • Production Manager: ensures warm-up and first-piece time is planned into the schedule; never authorizes running production ahead of inspector verification.
  • Manufacturing Engineer: maintains the control plan and the WU-10 program.

5 Procedure

5.1 Machine startup

  1. Confirm safety glasses with side shields and safety-toe shoes are worn (EHS-02). Do not wear gloves near rotating spindles.
  2. Check way-lube and coolant levels, air pressure, and that the work area is free of loose tools and debris (QP-7.7).
  3. Run WU-10 at the start of each shift and whenever the machine has been idle for more than 2 hours. Do not shorten or skip the 10-minute cycle.
  4. Confirm all gages to be used carry a green calibration label and are within their due date (QP-7.6). A yellow-label gage may only be used within the restriction written on its label.

5.2 Setup verification

  1. Verify the traveler, drawing revision and NC program revision match each other and the ERP job.
  2. Verify that tool offsets and work offsets have been set and recorded on the setup sheet.
  3. If the job is flagged "ITAR" on the traveler, keep the drawing at the machine and return it to the controlled location at end of shift (EXP-01).

5.3 First-piece check by the operator

  1. Run one part and measure 100% of the dimensional and visual characteristics listed on the control plan.
  2. Record actual values on the traveler, not just pass/fail.
  3. Deburr the part to WI-305 before visual evaluation.
  4. If any characteristic is out of tolerance, adjust and run another first piece. The rejected piece is red-tagged per WI-610.

5.4 Inspector verification

  1. The operator calls a Quality inspector, who independently re-measures the characteristics marked as key or critical on the control plan and reviews the operator's recorded results.
  2. When satisfied, the inspector stamps and dates the first-piece block on the traveler.
  3. Production on flight hardware must not start until the inspector stamp is on the traveler. There are no exceptions for rush orders or 2nd-shift staffing.
  4. If an FAI is required for the job (QP-8.6), the first piece is also sent to the Bay 4 metrology lab for CMM inspection per WI-210.

5.5 In-process checks

  1. Perform in-process checks at the frequency stated in the control plan.
  2. If the control plan does not specify a frequency, the default is every 10th part or once per hour, whichever is more frequent.
  3. Record each check on the traveler with part count, time and initials.

5.6 Failed in-process check

  1. Stop the machine immediately. Do not continue the run to "finish the bar" or the batch.
  2. Apply a red HOLD tag (F-750-04) to the failed part and to every part produced since the last good check, and quarantine them per WI-610.
  3. Notify the shift lead and Quality. Quality enters the NCR per QP-7.5.
  4. Do not restart until the cause is corrected and a new first piece has been approved per 5.3 and 5.4.

6 Records

The traveler, including first-piece results, inspector stamp and in-process check entries, is a quality record retained 10 years from creation per QP-4.2. NCRs generated under 5.6 are retained per QP-7.5.

7 Revision history

Rev Date Change Approved by
C 2021-04-05 Added control plan reference for in-process frequency Ruth Okafor
D 2023-06-12 Added default in-process frequency (every 10th part or hourly) Ruth Okafor
E 2025-08-11 Inspector verification made mandatory before production on flight hardware; WU-10 required after 2 hours idle Ruth Okafor