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M48 × 2 Thread Dimensions & Specifications

M48 ×2 Thread Overview

When precision matters more than speed, M48 × 2 fine threads deliver superior performance. Unlike coarse alternatives, this metric fine thread configuration provides:

  • Enhanced Positioning Accuracy– more engaged threads within the same mounting length
  • Smoother Adjustment Resolution– Finer pitch enables micro-adjustments in optical and mechanical systems
  • Reduced Vibration Loosening– Greater thread engagement increases resistance to self-loosening under dynamic loads
  • Space-Efficient Design– Achieves higher clamping force without requiring additional axial length

Industries leveraging M48 × 2: precision optics, medical devices, instrumentation, aerospace components, and calibration equipment.

M48 × 2 Thread Dimensions

Schematic of basic thread dimensions for LCA threaded feed‑through EMI filter, illustrates major diameter, pitch, pitch diameter, minor diameter, thread height and 60° thread profile

ParameterSpecification
Thread StandardISO Metric Threads
Major Diameter48.0mm1.8898 in
Pitch2 mm0.0787 in
Pitch Diameter46.701 mm1.8386 in
Minor Diameter45.835 mm1.8045 in
Thread Height1.083 mm0.0426 in
Addendum0.65 mm0.0256 in
Thread Angle60°

Understanding the M48 × 2 Designation

The designation identifies the basic geometry of the thread:

  • M= ISO Metric Thread
  • 48= Nominal major diameter of 48 mm
  • 2= Thread pitch of 2 mm

The pitch should be stated when specifying the thread because the same nominal M48 diameter can be manufactured with different pitches. Writing M48 × 2 removes ambiguity during design, machining, and purchasing.

Characteristics of M48 × 2 Fine Thread

  • Smaller pitch than the standard M48× 5 coarse thread.
  • Finer axial adjustment and greater adjustment resolution.
  • More engaged threads over the same threaded length.
  • Useful where available axial space is limited.
  • Suitable for precision mechanical assemblies and fine adjustment mechanisms.

M48 × 2 Thread Tolerance Classes

Thread tolerance classes define the permissible dimensional variation and determine how mating external and internal threads fit together. ISO metric fine threads, a complete tolerance designation combines a numerical tolerance grade with a tolerance-position letter.

Example: M48 × 2 – 6g

  • 6 — Tolerance grade.
  • g — Tolerance position for an external thread.

The corresponding internal thread is typically specified as M48 × 2 – 6H.

Thread TypeCommon ClassTypical Application
External Thread6gGeneral-purpose screws and bolts
Internal Thread6HGeneral-purpose tapped holes and nuts
External Thread4g6gPrecision mechanical assemblies
External Thread8gLoose fit or coated fasteners
Internal Thread5HHigher positioning accuracy

When to Use M48 × 5 (Coarse) Instead

M48× 2 and M48 × 5 have the same nominal major diameter, but their pitches are different. The choice depends on the required assembly characteristics and application.

FeatureM48 × 2M48 × 5
Thread TypeFine threadStandard coarse thread
Pitch2 mm5 mm
AdjustmentMore preciseFaster
Thread EngagementMore threads per lengthFewer threads per length
AssemblySuitable for precision adjustmentGenerally easier and faster
Typical UsePrecision assemblies and fine adjustmentGeneral-purpose fastening

Typical Applications

M48 × 2 fine threads can be used in applications where controlled adjustment, positioning accuracy, or compact threaded engagement is required. Examples include:

Optical instruments

  • Precision measuring devices
  • Fine adjustment mechanisms
  • Precision mechanical assemblies

By comparison, M48×5 coarse threads are commonly selected for general-purpose fastening applications, including industrial equipment, enclosures, and control panels.

Frequently Asked Questions (FAQ)

Q1. Is M48 × 2 a standard thread?

Yes. M48 × 2 is a standardized ISO metric fine thread defined by ISO 965-1 and ISO 965-2. It is less common than M48 × 5 but fully recognized in international engineering standards and specifications.

Q2.What happens if I specify just “M48” on an engineering drawing?

Drawings specifying only “M48” default to M48 × 5 coarse thread. To ensure the fine-pitch version is used, explicitly write M48 ×2. This prevents costly manufacturing and procurement errors.

Q3: Can I substitute M48 × 2 with M48 × 5 in an existing assembly?

No. The different pitches produce incompatible thread geometries. Using M48 × 5 fasteners in M48 × 2 tapped holes will cross-thread and damage both components. Always match pitch specifications exactly.

Q4.What does 6g mean for an M48 × 2 thread?

6g is a commonly used tolerance designation for an external ISO metric thread, combining tolerance grade 6 with tolerance position g.

Q5.What is the typical internal-thread designation?

The corresponding internal thread is typically specified as M48 × 2 – 6H.

Q6. Can LCA provide EMI filters with M48 threads?

Yes. LCA supports customized mechanical designs involving metric and inch thread configurations.

Customization options include:

  • Thread size
  • Housing dimensions
  • Electrical parameters
  • Sealing structure
  • Plating options

Engineering Support CTA: Selecting a threaded EMI filter or feedthrough capacitor? Share the thread standard and size, panel thickness, voltage/current, capacitance, and environmental requirements with LCA engineers. View Thread Mount Feedthrough Filters

Related Engineering Resources

Thread Standards

Thread Specifications

Thread Guide

Customization

LCA is customer demand-centric. With professional technical capabilities, rigorous implementation processes, and considerate full-cycle services, it creates exclusive solutions for customers with diverse needs!