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Mini lathe/Gingery lathe metric change gears by cae2100
by Thingiverse
Last crawled date: 4 years, 3 months ago
Gingery lathe has 3/8-16 threaded rod as leadscrew, which matches the 16tpi leadscrew on mini lathes, so using these tables, you can cut either metric or imperial threads on the gingery lathe and mini lathes with 16tpi leadscrews.
http://www.arceurotrade.co.uk/reviews/MEW204-P31_P36-Thread-Cutting.pdf
http://www.arceurotrade.co.uk/reviews/MEW204-P31_P36-Thread-Cutting.pdf