# Grinding, Lapping, Polishing, and Buffing Machine Tool Setters, Operators, and Tenders, Metal and Plastic

US SOC code 51-4033. Markdown version of https://futurehistory.earth/timeline/51-4033

Also called: Grinding machine operator, Polishing machine operator, Buffing machine operator, Surface grinder operator, Lapping machine tender.

## In brief

In May 2025, [BLS](https://www.bls.gov/oes/special-requests/oesm25nat.zip) counted **67,000** US metal and plastic grinding, lapping, polishing, and buffing machine tool setters, operators, and tenders, with median pay of **$46,550** a year. Of the BLS counts since 2003, the highest was **101,530**, in May 2005. The earliest figure here is [an estimate](https://ledger.americanprecision.org/profile/charles-h-norton/) of **40,000** from 1900, not measured the same way as today's count. The last full technology era in this work: CNC grinding centers, 1985 to 2015. CNC grinding automation, combined with deindustrialization and offshoring of consumer-goods finishing to Asia, drove a sustained employment decline between 1990 and 2003 and continued falling.

## What the sources say

### Official outlook

BLS projects employment to decline 10.8% from 2025 to 2035. Source: [BLS Employment Projections 2025-35](https://data.bls.gov/projections/nationalMatrix?queryParams=51-4033&ioType=o).

### AI exposure studies

- **6.5%** of this job's tasks are exposed to large language models. Not a forecast of job losses. [Eloundou and others, 2023](https://github.com/openai/GPTs-are-GPTs/blob/main/data/occ_level.csv)
- **0.95** estimated probability that the whole occupation could be computerised, over an unspecified number of years. Not a forecast of job losses. [Frey and Osborne, 2013](https://oms-www.files.svdcdn.com/production/downloads/academic/The_Future_of_Employment.pdf)

### Since the 2013 prediction

In 2013, Frey and Osborne put this job's probability of computerisation at 0.95. BLS counted **70,910** of these jobs in May 2013 and **67,000** in May 2025 (-6%, a change derived by Future History).

Data as of BLS OEWS May 2025; BLS Employment Projections 2025-35. BLS publishes these counts as yearly survey snapshots and cautions against reading them as a precise trend. In May 2021 BLS changed how it estimates these counts (a model-based method using three years of survey data) and moved fully to the 2018 occupation codes, so part of a change across 2021 can come from the method rather than the work.

## Grinding, Lapping, Polishing, and Buffing Machine Tool Setters, Operators, and Tenders, Metal and Plastic employment and pay by year

- On record since: 1874
- Latest US employment: 67,000 (May 2025). Source: BLS OEWS May 2025 [5]
- Latest US median pay: $46,550 (May 2025). Source: BLS OEWS May 2025 [11]
- Outlook: -10.8% by 2035. Source: BLS Employment Projections 2025-35 [28]

### In other countries

The latest figure each country's statistics agency publishes for this job. Each uses its own occupation definition, survey basis and currency, so the numbers are not directly comparable with each other or with the US figures.

- **Canada** (NOC 94106)
  - Employment, 2020: 8,665. Source: Statistics Canada Census 2021 [8]. Statistics Canada Census of Population 2021: number of persons with employment income in NOC 94106 Machining tool operators, Canada, reference year 2020. A recipients basis (anyone with employment income during the year), slightly broader than a point-in-time employed count. Statistics Canada Open Licence.
  - Median pay, 2020: C$53,600. Source: Statistics Canada Census 2021 [14]. Statistics Canada Census of Population 2021 (Table 98-10-0586): median employment income for NOC 94106 Machining tool operators, Canada, reference year 2020, full-year full-time workers (the basis comparable to the US OEWS full-time median). Statistics Canada Open Licence.

### All 28 years of cited US data

| Year | US employment | Annual pay (median unless marked) | Source |
| --- | --- | --- | --- |
| 1900 | 40,000 (estimate) | n/a | Est., Charles H. Norton [1] |
| 1943 | 250,000 (estimate) | n/a | Est., Arter Precision Grinding Machines [2] |
| 1953 | 200,000 (estimate) | $3,900 | Est., FRASER / BLS Bulletin 1130 [3] |
| 1990 | 130,000 (estimate) | n/a | Est., BLS [4] |
| 2000 | n/a | $24,360 | BLS OEWS 2000 [10] |
| 2003 | 97,660 | $26,630 | BLS OEWS May 2003 [5] |
| 2004 | 98,770 | $27,440 | BLS OEWS May 2004 [5] |
| 2005 | 101,530 | $27,740 | BLS OEWS May 2005 [5] |
| 2006 | 100,010 | $28,080 | BLS OEWS May 2006 [5] |
| 2007 | 96,730 | $28,640 | BLS OEWS May 2007 [5] |
| 2008 | 91,990 | $29,460 | BLS OEWS May 2008 [5] |
| 2009 | 81,740 | $30,270 | BLS OEWS May 2009 [5] |
| 2010 | 70,120 | $30,670 | BLS OEWS May 2010 [5] |
| 2011 | 70,450 | $31,280 | BLS OEWS May 2011 [5] |
| 2012 | 69,510 | $31,620 | BLS OEWS May 2012 [5] |
| 2013 | 70,910 | $32,220 | BLS OEWS May 2013 [5] |
| 2014 | 70,130 | $32,660 | BLS OEWS May 2014 [5] |
| 2015 | 73,570 | $32,840 | BLS OEWS May 2015 [5] |
| 2016 | 74,600 | $32,890 | BLS OEWS May 2016 [5] |
| 2017 | 74,600 | $33,480 | BLS OEWS May 2017 [5] |
| 2018 | 71,870 | $34,850 | BLS OEWS May 2018 [5] |
| 2019 | 76,810 | $36,100 | BLS OEWS May 2019 [5] |
| 2020 | 69,570 | $36,880 | BLS OEWS May 2020 [5] |
| 2021 | 67,750 | $37,550 | BLS OEWS May 2021 [5] |
| 2022 | 73,800 | $38,910 | BLS OEWS May 2022 [5] |
| 2023 | 75,260 | $42,610 | BLS OEWS May 2023 [5] |
| 2024 | 70,110 | $45,190 | BLS OEWS May 2024 [5] |
| 2025 | 67,000 | $46,550 | BLS OEWS May 2025 [5] |

## Sources (91)

### Employment series

1. [Charles H. Norton — Manufacturing Ledger (American Precision Museum): career narrative and impact on grinding workforce](https://ledger.americanprecision.org/profile/charles-h-norton/), American Precision Museum / Manufacturing Ledger
2. [Arter Precision Grinding Machines: written history — WWII mobilization and grinding machine production](https://www.artergrinder.com/post/arter-precision-grinding-machines-a-written-history-of-over-a-century-of-top-notch-grinding), Arter Grinder
3. [FRASER / BLS Bulletin 1130 — Employment Outlook in Metalworking Occupations (1953)](https://fraser.stlouisfed.org/files/docs/publications/bls/bls_1130_1953.pdf), Bureau of Labor Statistics / FRASER
4. [BLS — Forty Years of Falling Manufacturing Employment (Beyond the Numbers, 2020): manufacturing employment trends 1980-2020](https://www.bls.gov/opub/btn/volume-9/forty-years-of-falling-manufacturing-employment.htm), Bureau of Labor Statistics
5. BLS OEWS, national cross-industry estimates (flat file), Bureau of Labor Statistics. Editions: [2003](https://www.bls.gov/oes/special-requests/oesm03nat.zip), [2004](https://www.bls.gov/oes/special-requests/oesm04nat.zip), [2005](https://www.bls.gov/oes/special-requests/oesm05nat.zip), [2006](https://www.bls.gov/oes/special-requests/oesm06nat.zip), [2007](https://www.bls.gov/oes/special-requests/oesm07nat.zip), [2008](https://www.bls.gov/oes/special-requests/oesm08nat.zip), [2009](https://www.bls.gov/oes/special-requests/oesm09nat.zip), [2010](https://www.bls.gov/oes/special-requests/oesm10nat.zip), [2011](https://www.bls.gov/oes/special-requests/oesm11nat.zip), [2012](https://www.bls.gov/oes/special-requests/oesm12nat.zip), [2013](https://www.bls.gov/oes/special-requests/oesm13nat.zip), [2014](https://www.bls.gov/oes/special-requests/oesm14nat.zip), [2015](https://www.bls.gov/oes/special-requests/oesm15nat.zip), [2016](https://www.bls.gov/oes/special-requests/oesm16nat.zip), [2017](https://www.bls.gov/oes/special-requests/oesm17nat.zip), [2018](https://www.bls.gov/oes/special-requests/oesm18nat.zip), [2019](https://www.bls.gov/oes/special-requests/oesm19nat.zip), [2020](https://www.bls.gov/oes/special-requests/oesm20nat.zip), [2021](https://www.bls.gov/oes/special-requests/oesm21nat.zip), [2022](https://www.bls.gov/oes/special-requests/oesm22nat.zip), [2023](https://www.bls.gov/oes/special-requests/oesm23nat.zip), [2024](https://www.bls.gov/oes/special-requests/oesm24nat.zip), [2025](https://www.bls.gov/oes/special-requests/oesm25nat.zip)
6. [Statistics Canada, Census of Population 2006, Table 97-563-XCB2006069 (Wage and salary statistics by occupation, NOC-S 2006), income reference year 2005](https://www12.statcan.gc.ca/census-recensement/2006/dp-pd/tbt/Rp-eng.cfm?LANG=E&PID=96285), Statistics Canada
7. [Statistics Canada, Census of Population 2016, Table 98-400-X2016356 (Occupation by employment income statistics, NOC 2016), income reference year 2015](https://www150.statcan.gc.ca/n1/en/catalogue/98-400-X2016356), Statistics Canada
8. [Statistics Canada, Census of Population 2021, Table 98-10-0586 (Employment income statistics by occupation unit group, NOC 2021), income reference year 2020](https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=9810058601), Statistics Canada

### Wage series

9. [FRASER / BLS Bulletin 1130 — Employment Outlook in Metalworking Occupations (1953): earnings data for metalworking operators](https://fraser.stlouisfed.org/files/docs/publications/bls/bls_1130_1953.pdf), Bureau of Labor Statistics / FRASER
10. [BLS OES 2000 national estimates (flat file)](https://www.bls.gov/oes/special-requests/oes00nat.zip), Bureau of Labor Statistics
11. BLS OEWS, national cross-industry estimates (flat file), Bureau of Labor Statistics. Editions: [2003](https://www.bls.gov/oes/special-requests/oesm03nat.zip), [2004](https://www.bls.gov/oes/special-requests/oesm04nat.zip), [2005](https://www.bls.gov/oes/special-requests/oesm05nat.zip), [2006](https://www.bls.gov/oes/special-requests/oesm06nat.zip), [2007](https://www.bls.gov/oes/special-requests/oesm07nat.zip), [2008](https://www.bls.gov/oes/special-requests/oesm08nat.zip), [2009](https://www.bls.gov/oes/special-requests/oesm09nat.zip), [2010](https://www.bls.gov/oes/special-requests/oesm10nat.zip), [2011](https://www.bls.gov/oes/special-requests/oesm11nat.zip), [2012](https://www.bls.gov/oes/special-requests/oesm12nat.zip), [2013](https://www.bls.gov/oes/special-requests/oesm13nat.zip), [2014](https://www.bls.gov/oes/special-requests/oesm14nat.zip), [2015](https://www.bls.gov/oes/special-requests/oesm15nat.zip), [2016](https://www.bls.gov/oes/special-requests/oesm16nat.zip), [2017](https://www.bls.gov/oes/special-requests/oesm17nat.zip), [2018](https://www.bls.gov/oes/special-requests/oesm18nat.zip), [2019](https://www.bls.gov/oes/special-requests/oesm19nat.zip), [2020](https://www.bls.gov/oes/special-requests/oesm20nat.zip), [2021](https://www.bls.gov/oes/special-requests/oesm21nat.zip), [2022](https://www.bls.gov/oes/special-requests/oesm22nat.zip), [2023](https://www.bls.gov/oes/special-requests/oesm23nat.zip), [2024](https://www.bls.gov/oes/special-requests/oesm24nat.zip), [2025](https://www.bls.gov/oes/special-requests/oesm25nat.zip)
12. [Statistics Canada, Census of Population 2006, Table 97-563-XCB2006069 (Wage and salary statistics by occupation, NOC-S 2006), income reference year 2005](https://www12.statcan.gc.ca/census-recensement/2006/dp-pd/tbt/Rp-eng.cfm?LANG=E&PID=96285), Statistics Canada
13. [Statistics Canada, Census of Population 2016, Table 98-400-X2016356 (Occupation by employment income statistics, NOC 2016), income reference year 2015](https://www150.statcan.gc.ca/n1/en/catalogue/98-400-X2016356), Statistics Canada
14. [Statistics Canada, Census of Population 2021, Table 98-10-0586 (Employment income statistics by occupation unit group, NOC 2021), income reference year 2020](https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=9810058601), Statistics Canada

### Tool eras

15. [Origins of Cylindrical Grinding — Indiana Precision Grinding: Brown and Sharpe 1874 commercial introduction](https://indianaprecisiongrinding.com/origins-of-cylindrical-grinding/), Indiana Precision Grinding
16. [Charles H. Norton — Manufacturing Ledger (American Precision Museum)](https://ledger.americanprecision.org/profile/charles-h-norton/), American Precision Museum
17. [Ford's secret weapon wasn't the assembly line — it was this Massachusetts grinding machine (Norton and Ford Model T)](https://wheninyourstate.com/connecticut/fords-secret-weapon-wasnt-the-assembly-line-it-was-this-massachusetts-grinding-machine/), When In Your State
18. [Norton Abrasives — History of Norton: company and technology timeline](https://www.nortonabrasives.com/en-gb/history-norton), Norton Abrasives
19. [Arter Precision Grinding Machines — written history of over a century of grinding (WWII section)](https://www.artergrinder.com/post/arter-precision-grinding-machines-a-written-history-of-over-a-century-of-top-notch-grinding), Arter Grinder
20. [The Tools of Production — National WWII Museum (machine tools and precision manufacturing in war production)](https://manufacturing-victory.org/history/tools.php), National WWII Museum
21. [History of Numerical Control — Wikipedia: MIT/Bendix NC development 1954 and spread to machine tools](https://en.wikipedia.org/wiki/History_of_numerical_control), Wikipedia
22. [BLS Monthly Labor Review 1982 — Shortages of Machinists: an evaluation of the information (1982)](https://www.bls.gov/opub/mlr/1982/07/art5full.pdf), Bureau of Labor Statistics
23. [Siemens SINUMERIK — CNC Grinding technology overview (cylindrical and surface grinding control systems)](https://www.siemens.com/en-us/products/sinumerik/), Siemens
24. [BLS — Forty Years of Falling Manufacturing Employment (Beyond the Numbers, 2020)](https://www.bls.gov/opub/btn/volume-9/forty-years-of-falling-manufacturing-employment.htm), Bureau of Labor Statistics
25. [GrayMatter Robotics — Scan&Grind and Scan&Polish solutions (AI-guided robotic surface finishing)](https://graymatter-robotics.com/solutions/), GrayMatter Robotics
26. [Zivid — Case Study: GrayMatter Robotics AI-Powered Robotic Surface Finishing](https://www.zivid.com/application-stories/case-study-graymatter-robotics-ai-powered-robotic-surface-finishing), Zivid
27. [CompositesWorld — AI-powered robotic solutions support high-mix manufacturing (GrayMatter aerospace applications)](https://www.compositesworld.com/articles/ai-powered-robotic-solutions-support-high-mix-manufacturing), CompositesWorld

### Forecasts and exposure studies

28. [BLS Employment Projections 2025-35, National Employment Matrix: 51-4033 Grinding, lapping, polishing, and buffing machine tool setters, operators, and tenders, metal and plastic (2025: 68.5 thousand; 2035: 61.1 thousand; -10.8%)](https://data.bls.gov/projections/nationalMatrix?queryParams=51-4033&ioType=o), Bureau of Labor Statistics
29. [Frey & Osborne (2013), "The Future of Employment: How Susceptible Are Jobs to Computerisation?", Appendix (SOC 51-4033 Grinding, Lapping, Polishing, and Buffing Machine Tool Setters, Operators, and Tenders, Metal and Plastic: probability 0.95, rank 624 of 702)](https://oms-www.files.svdcdn.com/production/downloads/academic/The_Future_of_Employment.pdf), Oxford Martin School, University of Oxford
30. [Eloundou, Manning, Mishkin & Rock (2023), "GPTs are GPTs", occupation-level exposure data occ\_level.csv (O\*NET-SOC 51-4033.00, human-rated β 0.065)](https://github.com/openai/GPTs-are-GPTs/blob/main/data/occ_level.csv), OpenAI

### Historical notes

31. [Origins of Cylindrical Grinding — Indiana Precision Grinding (Brown and Sharpe 1874)](https://indianaprecisiongrinding.com/origins-of-cylindrical-grinding/), Indiana Precision Grinding
32. [Charles Hotchkiss Norton — Wikipedia: biography and grinding machine history](https://en.wikipedia.org/wiki/Charles_Hotchkiss_Norton), Wikipedia
33. [IGS — Lapidary Technology Through the Ages: Laps and Polish (industrial flat-lapping development in the 1930s)](https://www.gemsociety.org/article/lapidary-technology-history-laps-and-polish/), International Gem Society
34. [Machining for Freedom — American Machinist (WWII machine-tool production and grinding operators)](https://www.americanmachinist.com/archive/features/article/21893860/machining-for-freedom), American Machinist
35. [History of CNC Machining — Evolution to the Modern Day (MIT/Bendix NC development 1954)](https://yijinsolution.com/cnc-guides/cnc-machining-history/), Yijin Solution
36. [O\*NET 51-4033.00 — SOC 2000 classification and current occupation summary](https://www.onetonline.org/link/summary/51-4033.00), O\*NET / BLS
37. [GrayMatter Robotics — Physical AI Innovation Center launch (October 2025)](https://www.prnewswire.com/news-releases/graymatter-robotics-unveils-100-000-square-foot-ai-robotics-innovation-center-in-carson-302592147.html), GrayMatter Robotics / PR Newswire

### Predecessors & successors

38. [Origins of Cylindrical Grinding — Indiana Precision Grinding: hand-grinding craft giving way to machine operation](https://indianaprecisiongrinding.com/origins-of-cylindrical-grinding/), Indiana Precision Grinding

### Present-day analysis

- [O\*NET 30.3 — Grinding, Lapping, Polishing, and Buffing Machine Tool Setters, Operators, and Tenders (51-4033.00)](https://www.onetonline.org/link/summary/51-4033.00), accessed 2026-06-05
- [BLS OOH — Metal and Plastic Machine Workers (2024-2034 projections: -7% category decline)](https://www.bls.gov/ooh/production/metal-and-plastic-machine-workers.htm), accessed 2026-06-05
- [GrayMatter Robotics — Physical AI Innovation Center launch, October 2025](https://www.prnewswire.com/news-releases/graymatter-robotics-unveils-100-000-square-foot-ai-robotics-innovation-center-in-carson-302592147.html), accessed 2026-06-05
- [Acme Manufacturing — Robotic Metal Finishing capabilities](https://acmemfg.com/robotic-metal-finishing/), accessed 2026-06-05
- [Eloundou et al. 2024 — GPTs are GPTs (Science)](https://arxiv.org/abs/2303.10130), accessed 2026-06-05
- [AMD Machines — 2025: The Year AI Transformed Manufacturing](https://amdmachines.com/blog/2025-the-year-ai-transformed-manufacturing/), accessed 2026-06-05
- [GrayMatter Robotics — Scan&Grind and Scan&Polish product suite](https://graymatter-robotics.com/solutions/), accessed 2026-06-05
- [Quality Assurance in Precision Grinding: Tools and Techniques — AB Precision](https://www.abprecision.com/post/quality-assurance-in-precision-grinding-tools-and-techniques), accessed 2026-06-05
- [AI Vision Inspection for Manufacturing: Automated Defect Detection Guide 2026](https://ifactoryapp.com/article/ai-vision-inspection-manufacturing-defect-detection), accessed 2026-06-05

How to read these figures: https://futurehistory.earth/methodology. Every figure links to its own source; gaps stay gaps.