# Precision Machining Tolerances: A Standards-Anchored Guide

> Precision Advanced Manufacturing explains how to specify, hold and verify machining tolerances — from ISO 2768 to GD&T and aerospace documentation.

**Published:** 2026-06-05 | **Updated:** 2026-10-29 | **Author:** precision
**URL:** https://precisionam.com/articles/precision-machining/precision-machining-tolerances/
**Type:** post

**Categories:** Precision Machining

![Precision Machining Tolerances: A Standards-Anchored Guide](https://blog.precisionam.com/wp-content/uploads/sites/56/2026/06/1780327135665-26acbcbf5b8c-1024x572.webp)

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## Content

*Last updated: October 21, 2026*

## Key Takeaways

- Precision machining tolerances define how far a feature may deviate from nominal while remaining functional and verifiable under ISO 2768-1, ISO 286 and ASME Y14.5-2018.
- Standard CNC machining typically holds ±0.005 in (±0.127 mm), precision CNC reaches ±0.001–0.002 in (±0.025–0.051 mm) and tighter bands below ±0.0005 in rely on processes such as wire EDM or jig grinding with advanced inspection.
- Four tolerance types, bilateral, unilateral, limit and ISO fit tolerances, support different design goals, while GD&T controls form, orientation, location and runout relative to datum reference frames.
- Over-tightening tolerances beyond functional need raises cost, extends lead time and increases scrap risk, so tight bands should focus on critical features such as bearing seats and sealing surfaces.
- Precision Advanced Manufacturing is an ITAR-registered, AS9100D and ISO 9001:2015 certified provider offering multi-axis CNC, Swiss-type machining and complete inspection documentation from prototype through full-rate production.

[Request a tolerance and manufacturability review](https://precisionam.com/request-a-quote/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)

## Standard Machining Tolerances in Millimeters and Inches

Three tolerance tiers cover most machined features in production work. Each range reflects what a process holds repeatably across a run, not a best-ever single part.

Standard CNC machining typically holds about ±0.005 in (±0.127 mm) at baseline cost and lead time. When a feature needs more control, precision CNC reaches about ±0.001–0.002 in (±0.025–0.051 mm), which covers most aerospace structural features and precision fits. Beyond that, wire EDM and jig grinding take over, with wire EDM holding ±0.013 mm (±0.0005 in) with a rough cut and one skim and ±0.005 mm (±0.0002 in) with additional skims, while jig grinding typically holds around ±0.002 mm.

![A five-axis CNC head machining a round metal workpiece.](https://cdn.aigrowthmarketer.co/1785163943949-293d9b0cce58.webp)**Five-axis machining reaches complex geometries in a single setup — fewer fixtures, tighter true position, and the repeatability aerospace and defense programs demand.**

A shop’s best-ever part differs from a process capability it can hold across a production run. [AS9100 programs targeting key characteristics require a process capability index (Cpk) of at least 1.33](https://nicerapidtooling.com/resources/cnc-machining-for-aerospace-parts-tolerances-and-process-controls). That requirement means the process must hit the tolerance with statistical margin that covers tool wear, thermal effects and fixture variation over time. Advertised machine resolution does not replace demonstrated Cpk derived from ongoing SPC data.

Several factors determine what a process can hold repeatably:

- Process capability and machine condition, including spindle accuracy, axis positioning and thermal stability
- Thermal expansion of the workpiece and machine structure
- Fixturing and workholding rigidity
- Material machinability and residual stress
- Tool wear drift over a production run
- Number of setups and datum-transfer error between operations
- Secondary operations such as finishing and coating

The machining tolerance ranges above reflect CNC machining performance documented across aerospace and industrial applications. For any feature where function depends on the tolerance, the critical question concerns what the process can prove across every unit in the run.

## How Tight Tolerances Change Process Requirements

±0.005 in (±0.127 mm) sits at the standard baseline for CNC machining. Anything tighter adds cost and lead time, so this baseline does not qualify as a loose callout. [±0.01 in is looser than the general tolerance for 3-axis CNC milling and turning, which typically falls near ±0.002–0.005 in (±0.05–0.13 mm), with ±0.001 in achievable as a precision band](https://www.davantech.com/cnc-machining-tolerances-explained-achieving-precision-and-accuracy/).

Whether a value counts as tight depends on the feature, the process, the material and the inspection method. [General-purpose commercial CNC shops typically hold ±0.005 in on basic parts, while aerospace structural work starts near ±0.001 in and fuel and hydraulic systems can require ±0.0001 in](https://le-creator.com/blog/aerospace-machining). A ±0.005 in callout on a clearance hole in aluminum is routine. The same callout on a bearing bore in titanium demands precision boring or reaming, in-process gauging and CMM verification.

![A CMM touch probe measuring a machined aluminum bracket.](https://cdn.aigrowthmarketer.co/1785164194032-a09872ce26c4.webp)**Every critical dimension is verified — CMM inspection and controlled quality workflows produce first-article and in-process data you can trace to each part.**

As tolerances move tighter, process and shop disciplines escalate in a defined sequence. Standard 3-axis CNC handles ±0.005 in. Reaching ±0.001–0.002 in requires multi-axis CNC, Swiss-type turning or precision boring with controlled fixturing and bore gauging. Holding ±0.0005 in typically requires environmental conditioning, machine warm-up sequences and stress relief between operations. Below that range, wire EDM, jig grinding and lapping enter the picture, along with temperature-controlled measurement environments and [CMM verification to accuracies of ±2 µm or better](https://nicerapidtooling.com/resources/cnc-machining-for-aerospace-parts-tolerances-and-process-controls).

## The Four Types of Tolerances and GD&T Basics

Knowing which tier a process can hold covers only half of specification work. The other half involves choosing the tolerance type that expresses design intent, and four types appear on machined-part drawings.

- **Bilateral tolerances** allow deviation in both directions from nominal, such as 25.000 ±0.025 mm, with a symmetric tolerance zone.
- **Unilateral tolerances** allow deviation in one direction only, such as 25.000 +0.025/0 mm, which often appears on bores where the lower limit defines the functional boundary.
- **Limit tolerances** state the upper and lower acceptable dimensions directly, such as 24.975–25.025 mm, which removes ambiguity about the acceptable range.
- **ISO fit tolerances** combine a fundamental deviation letter with an IT grade number, such as H7 or k6, per [ISO 286-1:2010 and ISO 286-2:2010](https://metronq.com/en/blog/it-tolerance-grades), defining both the position and width of the tolerance zone relative to nominal size.

ISO 286 fit selection matters most for bearing seats, sealing surfaces and locating pin bores. [H7/k6 serves as a standard transition fit for rolling bearing inner rings under normal load, H7/g6 serves as a clearance fit for plain bearings and precision slides and H7/p6 serves as a locational interference fit requiring press or thermal assembly](https://mechcodex.com/learn/machine-design/preferred-fits-selector). The fit designation communicates functional intent clearly to any machine shop worldwide. A drawing that states “press fit” without an ISO 286 callout leaves the actual interference undefined.

GD&T callouts and plus/minus tolerances answer different questions. Plus/minus controls the size of a feature. GD&T, governed by [ASME Y14.5-2018 (R2024)](https://asme.org/codes-standards/find-codes-standards/dimensioning-and-tolerancing/2018/print-book), controls form, orientation, location and runout relative to a defined datum reference frame. A hole can meet the diameter requirement and still sit out of position, and only a GD&T true position callout controls where the hole locates.

The 3/2/1 rule governs the minimum contact points required to constrain a part in a datum reference frame. [Three points on the primary datum constrain one translation and two rotations, two points on the secondary datum constrain one translation and one rotation and one point on the tertiary datum constrains the final translation](https://xometry.com/resources/machining/datum-in-gd-t). Fixture design applies this principle by placing rests, pins and locators against the designated datum features in their specified precedence order. Datum precedence matters, because reversing the order of datum letters in a feature control frame changes the measurement reference hierarchy and produces different inspection results for the same part. For repeatable fixturing and CMM inspection, the 3/2/1 scheme ensures the part seats the same way every time, which enables any tolerance to be verified.

## The Standards That Govern Precision Machining Tolerances

Three standards anchor most precision machining tolerance callouts on aerospace, defense and industrial drawings: ISO 2768-1 for general tolerances, ISO 286 for fits and ASME Y14.5 for GD&T.

[ISO 2768-1:1989](https://wevolver.com/article/iso-2768-general-tolerances-tables-classes-current-status) defines four general tolerance classes for linear and angular dimensions, f (fine), m (medium), c (coarse) and v (very coarse), applied by title-block designation to all drawing dimensions that carry no individual tolerance callout. It applies to parts produced by metal removal or formed from sheet metal. [ISO 2768-1:1989 remains the current published edition, and ISO reviewed and confirmed it in 2022](https://wevolver.com/article/iso-2768-general-tolerances-tables-classes-current-status). Its catalog status lists stage 90.92, “International Standard to be revised,” with a forthcoming second edition at stage 60.00, “International Standard under publication.” Engineers should confirm the governing revision on each drawing, because the replacement edition will retitle and restructure the standard.

ISO 2768 general tolerances and individual tolerance callouts serve different purposes. General tolerances apply by default to noncritical dimensions where the workshop’s customary accuracy suffices. When a feature needs a tighter tolerance than the general class allows, an individual tolerance appears adjacent to the nominal dimension, and ISO 2768 no longer governs that feature. GD&T basic dimensions, indicated in rectangular frames, are also excluded from ISO 2768 general tolerances.

[ISO 2768-2:1989, which defined geometrical tolerance classes H, K and L, has been withdrawn and replaced by ISO 22081:2021](https://wevolver.com/article/iso-2768-general-tolerances-tables-classes-current-status). The H, K and L accuracy class designations no longer apply on current drawings.

[ISO 286-1:2010 and ISO 286-2:2010](https://metronq.com/en/blog/it-tolerance-grades) define the international tolerance and fit system for plain cylindrical and planar features up to 3,150 mm. [ISO 286 codifies 20 IT grades, IT01 through IT18, and 28 fundamental deviation letter codes](https://mechcodex.com/learn/machine-design/preferred-fits-selector). It applies dimension by dimension to features with a fit function, such as bearing seats, locating bores and sealing diameters, not to the drawing as a whole.

[ASME Y14.5-2018 (R2024)](https://asme.org/codes-standards/find-codes-standards/dimensioning-and-tolerancing/2018/print-book) serves as the governing U.S. standard for GD&T. It establishes symbols, rules, definitions and recommended practices for communicating geometric requirements on engineering drawings and digital product definitions and supersedes ASME Y14.5-2009.

## Process Capability Across Tolerance Tiers

Each tolerance tier maps to a defined set of processes and a corresponding inspection method. Specifying a tolerance without confirming that both the process and the inspection method can resolve it creates drawing risk.

Standard general tolerances, around ±0.005 in (±0.127 mm) and looser, fall within the domain of standard 3-axis CNC milling and turning. Inspection at this tier uses calipers and micrometers for accessible external dimensions and standard plug or pin gauges for feature-specific checks. [A measuring instrument should have an uncertainty of no more than about one-tenth of the tolerance](https://cncmachining-services.com/precision-cnc-machining-buyers-guide). That guideline removes calipers from tight-tolerance verification.

Precision CNC machining tolerances, around ±0.001–0.002 in (±0.025–0.051 mm), require multi-axis CNC machining, Swiss-type turning, precision boring or reaming. [Ordinary CNC finish turning achieves IT8–IT9, while precision turning with in-process gauging and tool-wear compensation reaches IT7 and IT6 on rigid machines](https://metronq.com/en/blog/it-tolerance-grades). Inspection at this tier uses bore gauges and pin gauges for feature-specific checks, with CMM inspection for complex geometry and multi-feature verification. [CMMs used in aerospace inspection measure complex three-dimensional geometries to accuracies of ±2 microns or better](https://nicerapidtooling.com/resources/cnc-machining-for-aerospace-parts-tolerances-and-process-controls), verifying both linear dimensions and GD&T characteristics in a single setup.

![Coolant spraying over a rotating cutter during CNC milling.](https://cdn.aigrowthmarketer.co/1785163924321-73fb4d714caf.webp)**Flood-cooled multi-axis milling clears chips fast and protects the cutting edge, keeping surface finish and dimensional accuracy consistent across long production runs.**

Tight and high-precision tolerances, around ±0.0002–0.0005 in (±0.005–0.013 mm), require wire EDM, jig grinding, precision cylindrical grinding or specialized finishing. [IT5 or tighter usually requires grinding, while honing or lapping reaches IT3–IT6](https://metronq.com/en/blog/it-tolerance-grades). Inspection at this tier requires CMM with temperature-controlled measurement environments, [air gauging resolving to 0.1 µm](https://mechcodex.com/learn/manufacturing/limits-fits-tolerances) or electronic bore gauges, because hand-held instruments cannot reliably discriminate at these bands.

Tolerance specification forms a three-way contract between design intent, the process that holds the band and the inspection method that verifies it. A tolerance no available method can verify becomes a drawing liability.

Precision Advanced Manufacturing supports this contract across the full tier landscape. Capabilities include advanced multi-axis CNC machining, Swiss-type machining, precision metal fabrication, specialty welding with thermal distortion control and integrated finishing, supported by in-house engineering, CNC programming and tooling development. In-process and final inspection with complete documentation closes the loop from first article through full-rate production.

For related coverage on tight-tolerance CNC work in Texas, see [Tight Tolerance CNC Texas: Certified Aerospace & Defense](https://precisionam.com/articles/tight-tolerance-cnc-texas/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent).

## Cost and Lead-Time Trade-offs of Tightening Tolerances

Tightening a tolerance beyond functional need raises cost, extends lead time and increases scrap and rework risk without adding performance.

The cost curve for tighter tolerances rises sharply. Moving from standard to precision tier requires different fixturing, slower feeds and more inspection time. Reaching the tight tier typically requires environmental conditioning, machine warm-up sequences and stress relief between operations. Each step adds cycle time, inspection burden and scrap exposure.

Secondary finishing compounds these effects. Electroless nickel plating typically adds 25 µm (0.001 in) per surface, so a slot or bore machined to nominal loses tolerance allowance from both sides after plating. [Type III hardcoat anodizing on aluminum adds 25–100 µm (0.001–0.004 in)](https://uneedpm.com/cnc-machining-surface-finishes-guide). That buildup creates tolerance risk on tight fits, threads and sealing features unless the design accounts for coating thickness. Conversion coatings such as Alodine add less than 1 µm and rarely threaten fit. Drawings should state clearly whether dimensions apply before or after finishing, because ambiguity creates inspection disagreements that become expensive after parts are made.

Engineering discipline reserves tight tolerances for functionally critical features such as bearing seats, sealing surfaces, locating bores and mating interfaces and applies general tolerances elsewhere. [IT7 provides sufficient control for most standard fits and offers an economical choice](https://technische-antriebselemente.de/en/guides/iso-fits-h7-h6). IT5 or IT6 should focus on rolling-bearing seats, precision spindles and demanding interference fits where the functional requirement demands that level.

For a deeper look at tolerance specification in the Austin-area context, see [CNC Machining Tolerances Austin: Specs, Costs, Verification](https://precisionam.com/articles/cnc-machining-tolerances-austin/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent).

## Aerospace and Defense Tolerance Documentation

On aerospace, defense and space programs, a tolerance callout carries weight only when documentation proves it was held. [AS9100D requires organizations to control the unique identification of outputs and retain documented information necessary to enable traceability when traceability is a requirement, and requires measuring equipment to be calibrated against traceable measurement standards when measurement traceability is a requirement](https://assem-tech.com/wp-content/uploads/2019/03/AS9100D.pdf). Traceability must appear in records.

![A commercial airliner in flight against a blue sky.](https://cdn.aigrowthmarketer.co/1785164215115-cf050b902241.webp)**Aerospace manufacturing for flight-critical hardware — machined and fabricated to AS9100D with the traceability and repeatability commercial airframe programs depend on.**

A supplier-quality engineer should expect specific evidence that a tolerance was held. Typical packages include in-process inspection records showing measurements taken during machining, final inspection records with dimensional results against drawing callouts, material certifications with heat number and mill test report traceability and, for first articles, a complete AS9102 First Article Inspection Report validating the manufacturing process before full-rate production.

Every aerospace component must remain traceable to its raw material source through material test reports and heat number documentation. [For serialized safety-critical items, records must be retained for the life of the program](https://nicerapidtooling.com/resources/cnc-machining-for-aerospace-parts-tolerances-and-process-controls). Tolerance stack-up analysis across multi-component assemblies plays a central role for systems such as landing gear and flight control linkages where dimensional errors accumulate across mating parts.

Precision Advanced Manufacturing is ITAR-registered and operates under AS9100D and ISO 9001:2015 certified quality management systems. Full documentation and traceability across materials and processes integrate into every production step, from prototype through full-rate manufacturing across its Anaheim, California and Texas locations. The documentation package a supplier-quality engineer receives reflects a system output from certified processes.

For a buyer’s perspective on evaluating aerospace precision machining suppliers, see [Aerospace Precision Machining in Texas: A Buyer’s Guide](https://precisionam.com/articles/aerospace-precision-machining-texas/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent) and [How To Evaluate Precision Machining Companies in Texas](https://precisionam.com/articles/precision-machining-companies-texas/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent).

## How Precision Advanced Manufacturing Supports Tolerance Control

Precision Advanced Manufacturing is an ITAR-registered, AS9100D and ISO 9001:2015 certified U.S. provider of complex, tight-tolerance machined components for commercial aerospace, military and defense, space and satellites, advanced industrials and UAV programs.

![A machined metal part fixtured inside a CNC machining center.](https://cdn.aigrowthmarketer.co/1785163886671-8f5217244f88.webp)**Mission-critical components leave no room for deviation. Multi-axis CNC machining holds tight tolerances part after part, with full material traceability behind every feature.**

The engagement model follows the three-way contract among design intent, process capability and inspection method. Engineering support and manufacturability review at the outset identify over-tightened features, confirm governing standards and refine the tolerance strategy before machining begins. Multi-axis CNC machining, Swiss-type machining and integrated finishing hold the tolerance through production. Rigorous in-process and final inspection with complete documentation, including material certifications, dimensional records and FAIR packages, proves the tolerance was held and provides the traceability aerospace and defense programs require.

The same validated quality carries from prototype to full-rate production without a supplier change or process revalidation. That continuity aligns with the needs of mission-critical programs.

[Connect with an expert and request a tailored quote](https://precisionam.com/request-a-quote/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)

## Frequently Asked Questions

### What Are Precision Machining Tolerances?

Precision machining tolerances define the allowable deviation from a nominal dimension that a machining process can hold repeatably and that an inspection method can verify. They appear in inch or metric units and follow standards such as ISO 2768-1, ISO 286 and ASME Y14.5-2018.

### What Are the Standard Tolerances for Machining?

Standard CNC machining tolerances typically sit near ±0.005 in (±0.127 mm) for general work. Precision CNC machining often holds around ±0.001–0.002 in (±0.025–0.051 mm). Tight or high-precision work may require bands below ±0.0005 in (±0.013 mm) using processes such as wire EDM, jig grinding or specialized finishing, depending on process, material, feature geometry and machine condition.

### What Are the Four Types of Tolerances?

The four types of tolerances on machined-part drawings are bilateral, unilateral, limit and ISO fit tolerances. Bilateral tolerances allow deviation in both directions from nominal. Unilateral tolerances allow deviation in one direction only. Limit tolerances state the upper and lower acceptable dimensions directly. ISO fit tolerances combine a fundamental deviation letter with an IT grade number per ISO 286, defining both the position and width of the tolerance zone.

### What Is the 3/2/1 Rule in GD&T?

The 3/2/1 rule is the planar datum locating principle that fully constrains a rigid body. It contacts the primary datum at three points, the secondary datum at two points and the tertiary datum at one point to remove all six degrees of freedom. This approach ensures the part seats identically in the fixture and on the CMM for repeatable inspection.

### How Do ISO 2768 General Tolerances Differ From Individual Callouts?

ISO 2768-1 general tolerances apply by title-block designation to all drawing dimensions that carry no individual tolerance, setting a default accuracy class, f, m, c or v, for the entire part. Individual tolerance callouts override ISO 2768 on a feature-by-feature basis and appear wherever the functional requirement is tighter than the general class allows or where an ISO 286 fit designation governs the feature.

### How Can a Buyer Confirm a Supplier Can Hold and Verify a Tolerance?

A buyer can request in-process and final inspection records from a comparable part, material certifications with heat number traceability and a First Article Inspection Report per AS9102. For key characteristics on critical programs, demonstrated process capability data, such as Cpk, should show that the process holds the tolerance with statistical margin across a production run.

## Conclusion and Practical Next Steps

A precision machining tolerance delivers value when design intent, process capability and inspection method align. The right tolerance is one that the process holds repeatably across a production run and that inspection can resolve with confidence.

Practical next steps include reviewing the drawing for over-tightened features that drive cost and lead time without adding performance, confirming the governing standards revision on each drawing, particularly for ISO 2768-1, and sending the drawing to a certified supplier for a manufacturability and tolerance review before production begins.

Precision Advanced Manufacturing serves as a first call for precision machining tolerances on mission-critical programs. The company is ITAR-registered, AS9100D and ISO 9001:2015 certified, with engineering support from the outset, multi-axis CNC and Swiss-type machining through production and complete inspection documentation from prototype to full-rate manufacturing. The contract among design, process and inspection is held and proven at every stage.

[Request A Quote Or Engineering Consultation](https://precisionam.com/request-a-quote/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)

## Read Next

- [Tight Tolerance Machining Standards: Complete Reference](https://precisionam.com/articles/tight-tolerance-machining-standards/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)
- [CNC Machining Tolerances: How to Specify and Verify](https://precisionam.com/articles/precision-cnc-machining-tolerances/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)
- [Tight Tolerance CNC Machining: A Practical Guide](https://precisionam.com/articles/tight-tolerance-cnc-machining/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)
- [Tight Tolerance Metal Components Machining: A Buyer’s Guide](https://precisionam.com/articles/tight-tolerance-metal-components-machining/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)
- [Multi-Axis Machining Tolerances: How To Specify Them](https://precisionam.com/articles/multi-axis-machining-tolerances-aerospace/?utm_term=precision-machining-tolerances&utm_campaign=ai_growth_agent)

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      - **Text:** Standard CNC machining tolerances typically sit near ±0.005 in (±0.127 mm) for general work. Precision CNC machining often holds around ±0.001–0.002 in (±0.025–0.051 mm). Tight or high-precision work may require bands below ±0.0005 in (±0.013 mm) using processes such as wire EDM, jig grinding or specialized finishing, depending on process, material, feature geometry and machine condition.
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      - **Text:** The four types of tolerances on machined-part drawings are bilateral, unilateral, limit and ISO fit tolerances. Bilateral tolerances allow deviation in both directions from nominal. Unilateral tolerances allow deviation in one direction only. Limit tolerances state the upper and lower acceptable dimensions directly. ISO fit tolerances combine a fundamental deviation letter with an IT grade number per ISO 286, defining both the position and width of the tolerance zone.
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      - **Text:** The 3/2/1 rule is the planar datum locating principle that fully constrains a rigid body. It contacts the primary datum at three points, the secondary datum at two points and the tertiary datum at one point to remove all six degrees of freedom. This approach ensures the part seats identically in the fixture and on the CMM for repeatable inspection.
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      - **Text:** ISO 2768-1 general tolerances apply by title-block designation to all drawing dimensions that carry no individual tolerance, setting a default accuracy class, f, m, c or v, for the entire part. Individual tolerance callouts override ISO 2768 on a feature-by-feature basis and appear wherever the functional requirement is tighter than the general class allows or where an ISO 286 fit designation governs the feature.
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  - **Headline:** Precision Machining Tolerances: A Standards-Anchored Guide
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---

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- **MCP Server (Streamable HTTP):** [https://precisionam.com/articles/.well-known/mcp](https://precisionam.com/articles/.well-known/mcp)

## Citations

- [CNC Machining Yield Rates: Benchmarks and Root Causes](https://precisionam.com/articles/precision-machining/cnc-machining-yield-rates-benchmarks/)
- [How to Hold and Prove Tight Tolerance Defense Machining](https://precisionam.com/articles/precision-machining/verify-tight-tolerance-defense-machining/)
- [How To Verify Precision CNC On-Time Delivery: A Playbook](https://precisionam.com/articles/precision-machining/precision-cnc-on-time-delivery/)
- [ITAR CNC Machining: How to Verify Tight Tolerances](https://precisionam.com/articles/precision-machining/itar-cnc-machining-tight-tolerances/)
- [How to Qualify Precision CNC Machining Companies](https://precisionam.com/articles/precision-machining/evaluate-precision-cnc-machining-companies/)

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