Yuasa 8 In. Model 550-008 3-Jaw Indexer Head With Tailstock

This used Yuasa Model 550-008 8-inch 3-jaw indexer head (serial number 93018) is designed for precision indexing applications in conjunction with rotary tables. Featuring an 8-inch diameter 3-jaw chuck, a 2.48-inch bore hole, and a 5.90-inch center height, it delivers full 360-degree rotation. The indexing mechanism utilizes a 24-position hardened and ground master plate paired with an adjustable vernier reading capable of accuracies within ±10 seconds. Built for high precision, the unit maintains tight tolerances including a base-to-chuck squareness of ±0.0008 inches, base parallelism of ±0.0004 inches, chuck concentricity of ±0.0005 inches, and mounting flange concentricity of ±0.0008 inches. The assembly includes an adjustable Yuasa Model 553-301 tailstock with a center height range from 5.31 inches to 6.69 inches. The unit comes complete with a chuck key, hardware, and indexing discs.