I don’t want to intrude upon Bill Phinn’s cycle thread discussion … but I would like to share this with fellow microscopists and anyone else with a serious interest in thread-forms and/or Imperial/Metric approximations.
https://www.photomacrography.net/forum/viewtopic.php?t=12404
It should be self-explanatory, so there may be no need for replies or discussion
… that’s fine by me.
MichaelG.
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Edit: __ incidentally, it’s interesting to note that Japanese standards are available at relatively modest prices.
https://www.standardssupply.com/product/JIS-B-7141-2012/