bkay, have you seen
https://www.youtube.com/watch?v=WxtQO2XSB4s ? There are some other videos specifically about 401 tensions (one has other bobbins, besides the 401):
https://www.youtube.com/watch?v=UttHpnQy0xk
https://www.youtube.com/watch?v=bTdSkkC4jtM
https://www.youtube.com/watch?v=MwiI_BXanJ8
Janey - Neat people never make the exciting discoveries I do.
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