Gauging guides.
Short, practical explainers on thread and plain gauging, written for anyone specifying or buying a gauge.
How a GO / NOT-GO Thread Gauge Works
A plain-language explanation of GO and NOT-GO thread gauge members and how they give a pass or fail decision.
Read the guideMetric vs Unified vs Pipe and Taper Threads
What metric, unified, parallel pipe and taper pipe thread standards each cover, and why the gauge has to match.
Read the guideHow to Choose the Right Thread Gauge
Three decisions when specifying a thread gauge: the standard, the class or tolerance, and plug vs ring.
Read the guidePlain Plug vs Snap Gauges: When to Use Which
The difference between plain plug/ring gauges and snap gauges, and which one fits internal vs external checks.
Read the guideWhat Traceable Calibration Means
What a traceable, NABL-accredited calibration certificate actually means and why it matters.
Read the guideWhat Is a Thread Gauge? Types and Uses
What a thread gauge is, the main types (plug, ring, taper, pitch, snap and plain gauges) and which one checks which feature.
Read the guideThread Plug Gauge vs Thread Ring Gauge
Thread plug gauge vs thread ring gauge: which checks an internal thread, which checks an external thread, and why both are used.
Read the guideMetric Thread Tolerance 6H and 6g Explained
What the metric thread tolerance classes 6H and 6g mean, how the letter and number are read, and why the gauge has to match the class.
Read the guideNPT vs BSPT vs G Pipe Threads
How NPT, BSPT and parallel G pipe threads differ in thread angle and sealing, and why each needs its own gauge.
Read the guideHow to Use a Thread Plug Gauge Correctly
Step by step: how to check an internal thread with a GO / NOT-GO thread plug gauge, and the mistakes that give a false result.
Read the guideHow to Read a Thread Designation (M10 × 1.5 6H)
What each part of a thread designation means, for metric (M10 × 1.5 6H) and unified (1/4-20 UNC-2A) threads, so you can specify the right gauge.
Read the guideGo/No-Go Gauge vs Micrometer: Which to Use
A go/no-go gauge gives a fast pass or fail, a micrometer gives a measured number. Here is when to use each on the shop floor.
Read the guideNPT vs NPTF: Dry-Seal Threads Explained
How NPTF dry-seal threads differ from NPT, why they need extra gauge members, and which standard each follows.
Read the guideACME vs Trapezoidal Threads: The Difference
ACME threads have a 29° angle to ASME B1.5 and trapezoidal threads a 30° angle to DIN 103-9. Why they need different gauges.
Read the guideHow to Choose a Snap Gauge
Single-end progressive, double-ended and I-type snap gauges: what each type is, the size range it covers and when to pick it.
Read the guideCan't find what you need?
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