Back in the early 1980's I bought a sewing machine at a yard sale . I thought cool it's only $20.00 ! Had a scrap of fabric under the needle where someone had sewed on it . Took it home , plugged it in . Nothing would move ! Crap ! Took the throatplate off and my god what a mess was in there . Pieces of thread , thread wrapped around the bobbin shuttle. But I started cleaning this out and a couple hours later . I kid you not a half a paper lunch sack full of lint and thread pieces ! Some of it was so compacted that it had gotten hard . After that a good oiling and it worked fine for a few more years . Also changed the needle . Annie