SOUTH BEND LATHE MODEL 9C ( 1937-1940 ) 80/63 METRIC TRANSLATION

pinshape

Summary Metric Translation gear for cutting metric threads on an imperial leadscrew lathe. Designed specifically for a South Bend lathe model 9C, this innovative tool is a game-changer for precision machining. Key Features * Teeth pressure angle: 14.5 degrees for optimal performance. * DP (Diametral Pitch) of 18 for efficient thread cutting. * Module of 1.411 for precise gear engagement. Gear Specifications * 63-tooth gear features an inside diameter of 75mm, slightly reduced to 74.4mm due to manufacturing tolerances. * 80-tooth gear boasts a designed inside diameter of 100mm, slightly decreased to 99.3mm during production. * A deliberate 1mm step is incorporated into the 63-tooth ring, creating a gap between gears approximately 3/8" wide plus an additional 1mm. Application Considerations * Space constraints often dictate which translation gear to use; other factors may also influence this decision. * Designs for a 127/100 metric translation gear are being uploaded, ensuring accurate pitch generation without errors. * The 80/63 gear set exhibits a minor error of 0.0125%, while the 47/37 set shows an error of -0.0212%. Print Settings * Rafts: disabled * Supports: not required * Resolution: optimized for precise thread cutting * Infill: 100% for added strength and durability Design Notes * The hardwood center I created was a practical choice due to availability, but form board or marine ply would be better options. * Timber was carefully turned to ensure the ABS ring fit snugly, then secured with super glue.