Repair manual Bernina 1001 or 1000-series?
Having problems with the bottom thread; on the top a straight stitch, on the bottom a rather loose "S"-shape bobbin thread. Tried all kinds of upper- and bobbin-tension settings, needles, threads. Hook seems to be on time; no "pick-up" issues. The feed-dogs seem on time. Top-tensioner seems to work fine too. Have 2x metal bobbin holders, tried with different bobbins (metal & plastic), tried all kinds of tensions; same result. I just can't figure out what causes the problem.
It would be nice to get a repair manual to check the settings / timings against my machine.
Has anybody a repair / service manual of the Bernina 1001? (the current Bernina 1008 model seems very identical)