Spi 14-444-4 Surface Finish Comparator 8 Specimen Nickel

Product Description

The SPI 14-444-4 is a nickel surface finish comparator used to visually and tactilely assess machined surface texture in fabrication and quality control environments. It covers a range of 0.4 to 50 Ra micrometers, equivalent to 16 to 2000 AA microinches, across 8 individual specimens produced by end milling. Machinists, quality inspectors, and CNC operators use this tool to compare finished workpiece surfaces against known reference standards without the need for electronic instrumentation. The comparator ships with an instruction sheet and a protective carrying case, making it ready for shop floor or inspection room use.

This comparator is suited for end milling applications in manufacturing and machine shop environments. It is used during in-process inspection and final part verification to ensure surface finishes meet drawing callouts and customer specifications. The 8-specimen format covers the most common end-milled surface finish values called out in aerospace, automotive, and general metalworking applications. Overall dimensions are 2.5 inches in length by 5 inches in width, keeping it compact enough for toolbox or bench storage.

Key Features

• 8 nickel specimens spanning 16, 32, 63, 125, 250, 500, 1000, and 2000 AA microinches (0.4 to 50 Ra micrometers)
• Calibrated for end milling machining process
• Dual-scale labeling in both AA microinch and Ra micrometer units
• Nickel material provides durable, corrosion-resistant reference surfaces
• Includes protective carrying case and instructions
• Complies with ANSI B46.1-1978, Military Specification 45662, and SAE standards

Compatibility

Designed as a reference standard for end milling surface finish inspection per ANSI B46.1-1978, Military Specification 45662, and SAE requirements. Suitable for use in any quality inspection workflow requiring AA microinch or Ra micrometer surface texture comparison.

Installation Notes

No installation is required. This is a handheld inspection reference tool. Store specimens in the included case to prevent surface contamination or damage that could affect comparative accuracy. Keep reference surfaces clean and free of oils or debris before use to ensure valid comparisons.