how do i aquire a metric threading chart for a 17" southbend turnado?

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"Dwain Martinson"
wrote in message ...
how do i aquire a metric threading chart for a 17" southbend
turnado?


I made a threading chart for my 10" SB that lacked the plate by
writing a spreadsheet which included the tumbler and banjo gear ratios
in the formulas. As I didn't know the gearbox innards I reverse
engineered the pitches from a photo of the gearbox plate.

I found that a 120/127 metric gear set would add more fine threads for
the optical stuff I was making than the standard 100/127 set.

-jsw