I was able to find a manual at
https://www.juki.co.jp/industrial_j/...u/menu_eg.html Click on
to download the manual.
It is in multiple languages. It looks like the adjustable thread guide with black screw is threaded like the second picture, but around the tension discs like in the first picture, as seen on page 23 of the pdf.
Janey - Neat people never make the exciting discoveries I do.
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