When does the thread advance off the spool and bobbin

[Lint]

For a shoe patcher sewing machine, when in the machine cycle does the thread come off the top thread spool?  Also same question for the bottom thread bobbin?  I have a Singer 29K and also one of the cheap Chinese shoe patchers. Is the answer the same for both machines? I am a novice at sewing machines and am just curious about what is happening when in the stitch cycle. I can observe the top thread spool directly, but not the bobbin.

[Wizcrafts]

53 minutes ago, Lint said:

For a shoe patcher sewing machine, when in the machine cycle does the thread come off the top thread spool?  Also same question for the bottom thread bobbin?  I have a Singer 29K and also one of the cheap Chinese shoe patchers. Is the answer the same for both machines? I am a novice at sewing machines and am just curious about what is happening when in the stitch cycle. I can observe the top thread spool directly, but not the bobbin.

It is always best to feed spooled thread off the top. Feeding sideways adds unpredictable friction that changes as the spool unwinds. If you need a thread stand, buy one. They come with raised bottom plates that screw onto a table. The stand threads into the plate and there are usually two cone brackets, and thread loops above them.

[nylonRigging]

1 hour ago, Lint said:

when in the machine cycle does the thread come off the top thread spool ?  Also same question for the bottom thread bobbin ? 

Thread advances 'Comes Off' the top thread spool, after every-time the Patcher foot makes contact.  Patcher Foot is the feed . The Thread advances 'Comes Off' as 'Needle Goes Up' same time the Patcher Foot feeds/drags the Thread and material behind for the beginning of next needles plunge with top thread.
'basically' .. Bobbin thread advances 'Comes Off' with every completed cycle of the Hook, and With the Needle Up-stroke pulling, and thread 'Comes Off' Bobbin .
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