Detailed and comprehensive Operation, Maintenance and Parts manual for the Less Bradner  7HD single spindle gear hobbing machine. The operation and maintenance manual includes sections on Lubrication

• Wiring
• Installation
• Operation
• Hob Centering
• In-Out Unit
• Headstock Adjustments
• Calculation of the Lead of Helical Gears
• Formula for
  • Main Drive Shaft
  • Index Worm
  • Hob RPM
  • Work Spindle Speeds
  • The parts manual consists of numerous labelled sectional drawings of each assembly.
  • Charts, Helical Gear Formulae and Index Diagrams showing which feed gears (changewheels)  to use and how, for spur gears, to arrange the drive system.