SOUTH BEND LATHE MODEL 9C ( 1937-1940 ) 127/100 METRIC TRANSLATION RING GEAR

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This is a Metric Translation gear designed for cutting metric threads on an Imperial Leadscrew Lathe, specifically created for a South Bend lathe model 9C. The photo shows an 80/63 translation gear as I doubt the 127/100 would fit my present setup - I need to make another banjo to make it work. The teeth have a 14.5 degree pressure angle and feature true involute form. The gear has a DP of 18 and a module of 1.411. The 127 tooth has a designed inside diameter of 165mm but ends up about 164mm, while the 100 tooth has a designed inside diameter of 127mm but measures about 126mm. The 100 tooth ring features a 1mm step, giving a gap between the gears that is 3/8" wide + 1mm. The 127 tooth ring is 3/8" wide, matching the width of standard South Bend gears. It's mainly space constraints that dictate which translation gear to use, although there may be other factors at play. The 127/100 metric translation gear yields no errors in generated pitches, while the 80/63 gives an error of 0.0125% and the 47/37 gear set results in an error of -0.0212%. Print Settings: Rafts - No; Supports - No; Resolution - I used a 0.3; Infill - 100%. The centre I created is made from hardwood, as that's what I had on hand, but form board or marine ply would likely be better options. I turned the timber so the ABS ring could slip over it, then covered it with super glue and ensured it ran true before the glue set.