Matrix (Coventry Gauge and Tool Company) No. 37 and No. 47 Type 2 Plunge-cut Thread Grinding Machines. Service and Maintenance Manual with Parts as Sectional Drawings and Dismantling Instructions. Stored FC2-D1
Matrix (Coventry Gauge and Tool Company) "Thread Grinding". Highly detailed publication titled: "Operator's Machine Hand book". Explains every detail of the process.