To clean a serger - remove the needle plate, needles, and competely unthread (this is my super thorough cleaning). I have one of those vacuum attachments for cleaning small things. I use that to suck out all the lint (NEVER blow the lint, it just blows it back into the gears of your machine, bad, bad, bad!) Then, I oil any moving grears, anywhere that something has to slide through something else.


Really, you can't over oil. Just use a drop or two though and don't put it anywhere that the thread runs through. Then, I take thick thread, like jeanstitch, put a few drops of alcohol on it and run it through each tension disc a few times.


For my machines, I do the same - remove needle, needle plate, bobbin casing. My bobbin casing then pops open and I clean and oil in there. Then I make sure the feed dogs are lint free.


Every few months dh unscrews the covers from the machines and cleans and oils the internal gears. Same thing, just put a drop of oil on everything that moves. You probably only need to do this one once a year if you aren't sewing a few hours a day like me.


Don't be afraid of your machine. You aren't going to break it by cleaning it. Just don't use any cleaners on it and don't take anything apart. Taking the cover off it okay, but don't remove anything on the inside, it throws off the timing.


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