Spi 34-299-8 Plug Thread Gage 9/16-18 6H No Go

Product Description

The SPI 34-299-8 is a single-end No Go plug thread gage used to verify internal thread conformance to a 9/16-18 UNF thread form at 6H tolerance class. It is manufactured from steel for durability and dimensional stability under repeated use in production or inspection environments. The gage is designed to reject threaded holes that fall outside the maximum material condition limit, making it a critical tool in quality control workflows. A Size 3 handle is required for use but is not included with this gage. The 34-299-8 ships with NIST traceability certification, supporting documentation requirements in regulated inspection environments.

This plug thread gage is suited for use in manufacturing, machining, and mechanical assembly environments where internal thread verification is required. Typical applications include incoming inspection of threaded components, in-process quality checks on machined parts, and final inspection of assemblies where 9/16-18 threaded holes must meet ANSI standards. The No Go member is used after a Go gage confirms the thread is within minimum material limits, confirming the hole has not been overtapped or otherwise cut beyond tolerance. Machinists, quality technicians, and inspection personnel are the primary users.

Key Features

• No Go plug member for 9/16-18 UNF internal thread inspection at 6H tolerance class
• Steel construction for dimensional stability and wear resistance under repeated use
• Single-end design fits a standard Size 3 thread gage handle (handle sold separately)
• Includes NIST traceability certification to support regulated inspection and calibration records
• Meets ANSI and NIST standards for thread gage manufacture and calibration

Compatibility

Designed for use with a standard Size 3 plug thread gage handle. Intended to inspect internal threads dimensioned to 9/16-18 UNF at 6H tolerance class per ANSI standards.

Installation Notes

Thread plug gages are installed and operated by quality technicians or machinists during inspection procedures. The gage must be mounted in a compatible Size 3 handle before use. Do not force the No Go member into a threaded hole; hand-tight insertion under light torque is the correct technique. Handle and gage should be kept clean and free of chips or debris to prevent false readings and gage wear.