Industrial sewing explained for upholsterers. Most of what is written about these machines is aimed at sailmakers, leatherworkers or garment factories — this is the same ground from an upholstery bench.
Thread
Bonded nylon or polyester, Tex sizes and the three numbering systems, which thread for which job, and the twist question.
Needles
Needle size by thread size, needle systems, round and leather points, and why a blunt needle causes skipped stitches.
Thread & needle selector
Answer three questions and get the thread, size, needle and stitch length for the job.
NextMachines
Walking foot, compound and needle feed, cylinder arm, flat bed — explained for upholsterers rather than sailmakers.
ComingTroubleshooting
Fraying, skipped stitches, uneven tension, puckering, thread breaks.
ComingSetup & parts
Presser feet, servo against clutch motors, speed reducers, tension and timing.
ComingWhere to start. If something is going wrong at the machine, it is thread or needle far more often than tension. The two guides above answer most of it, and the pairing between them answers most of the rest.
This section is being built out. Thread and needles are done; the selector, machines, troubleshooting and setup follow.