Provenance register
Technical Source Register
Every production record must point to a registered source or a documented formula. Restricted standards are identified without copying their protected tables.
Standards identity and scope
The register identifies the governing standards used to name thread families and explain scope. It does not reproduce protected tolerance tables.
| Designation | Edition | Scope used here |
|---|---|---|
| ASME B1.1-2024 Unified Inch Screw Threads (UN, UNR, and UNJ Thread Forms) | 2024 | Thread-family identity and terminology only; protected dimensional tables are not reproduced. |
| ISO 261:1998 ISO general purpose metric screw threads — General plan | 2 (1998), confirmed current in 2024 | Metric series identity only; protected dimensional and tolerance tables are not reproduced. |
| ASME B1.20.1-2013 (R2018) Pipe Threads, General Purpose, Inch | 2013, reaffirmed 2018 | NPT/NPS family identity and public scope only; protected dimensions and gauging tables are not reproduced. |
Registered documents
| Source | Type | Supports | Access / rights note |
|---|---|---|---|
| SI Units – Length National Institute of Standards and Technology | official-publication |
| Accessed 2026-11-09 U.S. government information; exact inch definition used as a conversion constant. |
| Fastener Design Manual, NASA RP-1228 National Aeronautics and Space Administration | official-publication |
| Accessed 2026-11-09 U.S. government work; public use permitted by the NASA record. |
| Cle-Line C01112 Tap and Drill Recommendations Greenfield Industries / Cle-Line | manufacturer-documentation |
| Accessed 2026-11-09 Referenced for individual manufacturer recommendations; the catalog table is not reproduced wholesale. |
| ASME B1.1 Unified Inch Screw Threads ASME | standard-register |
| Accessed 2026-11-09 Copyrighted standard. ThreadSizeGuide records its identity but does not reproduce restricted tolerance tables. |
| Decimal Equivalent & Drill Size Chart Travers Tool Co. | manufacturer-documentation |
| Accessed 2026-11-09 Referenced for individual number and letter drill dimensions; page text and layout are not reproduced. |
| ISO 261 ISO general purpose metric screw threads — General plan International Organization for Standardization | standard-register |
| Accessed 2026-11-09 Copyrighted standard. Only the standard identity and generally used designations are referenced. |
| Guide to Tap Drill Sizes — Forming Taps, UNC OSG Europe Logistics | manufacturer-documentation |
| Accessed 2026-11-10 Referenced for individual manufacturer forming-tap pre-hole ranges; the chart presentation is not reproduced. |
| A-XPF Highly Efficient Multi-Purpose Forming Tap OSG Canada | manufacturer-documentation |
| Accessed 2026-11-10 Product-specific manufacturer data used to independently check selected forming-tap ranges. |
| Tapping Sizes and Clearance Holes TR Fastenings | manufacturer-documentation |
| Accessed 2026-11-10 Individual documented recommendations are presented in an original data model; the source table layout is not copied. |
| ASME B1.1-2024 Unified Inch Screw Threads ASME | standard-register |
| Accessed 2026-11-10 Copyrighted standard. Only edition identity and scope are registered; protected tables are not reproduced. |
| ASME B1.20.1-2013 (R2018) Pipe Threads, General Purpose, Inch ASME | standard-register |
| Accessed 2026-11-10 Copyrighted standard. Only edition identity and public scope information are registered. |
| NASA Robotics Alliance Project Design Guide, Appendix C — Hole Size Charts NASA Robotics Alliance Project | official-publication |
| Accessed 2026-11-10 U.S. government technical publication used as an independent reference-case check. |
Data coverage
Straight threads57
Pipe comparisons1
Clearance sizes26
Drill series3
Dataset 2026.11.10-2; review date 2026-11-10. Source availability and standard editions require periodic review.