AI Appraisal Estimate

This item is a set of change gears and a threading chart, likely for a metalworking lathe or similar machine. The set includes at least six various-sized gears, predominantly black or dark grey, suggesting a material like cast iron or steel with an oxidized, perhaps blued or painted, finish. Each gear features a central bore with a keyway, enabling them to be mounted on shafts for power transmission. Their outer edges are toothed, indicating their function in a gear train system. Some gears show signs of wear, particularly on the teeth, and a visible accumulation of dust or grime. The threading chart is a rectangular metal plate, black with white or light-colored text and diagrams. It displays a 'THREADING CHART' title, part number 'P93-100', and intricate tabular data with gear train diagrams, indicating settings for various thread pitches. There are also visible mounting holes on the chart. The overall condition of the components suggests age and regular use, with some surface corrosion or patina on the gears and possibly some fading or scratching on the chart's surface. The items are housed in what appears to be an old box, possibly a cigar box, with 'Haddon Hall' and 'D. EMIL KLEIN CO. MAKERS NEW YORK' printed on the inside lid/rim, which provides a potential clue to their storage or origin, though not necessarily the manufacturer of the gears themselves. The style and nature of these components point to mechanical tooling from the mid-20th century or earlier.

I have examined the provided images of this Lathe Change Gear Set with Threading Chart. **Condition and Authenticity Assessment:** The gears appear to be original components, likely cast iron or steel, showing typical signs of age and regular use with surface wear, and some localized corrosion or patina on the teeth. The threading chart, a critical component, also appears authentic, with legible text and diagrams, consistent with older machine tooling. The 'Haddon Hall' cigar box, while not original packaging for the gears, provides a charming, albeit anecdotal, storage history, possibly linking them to incidental reuse typical of workshops. **Market Conditions and Comparables:** The market for vintage machine parts, especially for established brands of lathes, sees consistent demand from hobbyists, restorers, and small workshops. Individual gears tend to be less valuable than complete, matched sets. A complete set with an accompanying chart in this condition would typically fetch a higher price. Similar used sets, often sold on specialized forums or auction sites like eBay, can range significantly based on completeness, specific lathe model compatibility, and condition. **Demand and Rarity Considerations:** While not exceedingly rare, finding a complete set of change gears, along with its original threading chart, in functional condition is increasingly uncommon. This set's value is enhanced by the presence of the chart, which is essential for actual use. The 'P93-100' part number on the chart might allow for identification of the specific lathe it belongs to, which can either broaden or narrow its appeal and impact value. **Limitations and Further Verification:** A significant limitation of this appraisal is the lack of physical inspection. I cannot definitively assess the gears for excessive wear, cracks, or damage to the keyways that would affect functionality. The accuracy of the chart's data, although visually clear, cannot be tested. In-person examination would be needed to test gear engagement, assess the precision of the teeth, confirm material composition, and thoroughly inspect for hidden defects. Provenance documentation, such as service records or original lathe information, would further authenticate the set's history and specific application, which would certainly enhance its value.