TAMRON - Tamron M42 AdaptMaticMount

Comprehensive repair manual for Tamron M42 Adapt-a-Matic mounts, focusing on diagnosis and correction of defective aperture control mechanisms in "For Pentax II" variants and P-CS models produced between 1969 and 1973. This workshop manual documents the root causes of automatic aperture system failure—specifically misaligned actuating pins and improperly positioned lever arms that render the mount inoperative. The guide provides detailed comparative analysis between original defective mounts and corrected versions, supported by extensive photographs revealing galling marks, lever arm misalignment, and incorrect component positioning. Technical sections distinguish between the robust P-CS model with its larger flat pin base and the later revised version featuring a smaller pin diameter. Realignment procedures for contact arms and internal roller mechanisms are thoroughly detailed to enable successful restoration of mounts damaged by improper installation or assembly. The documentation covers structural differences in mount construction, spring assemblies, roller bearing contact points, and the mechanical interaction between all moving parts. An essential troubleshooting and repair resource for vintage lens mount collectors and restoration specialists working with Adapt-a-Matic systems.