Click on the picture to get a close up view.
So I cleaned, and cleaned, and cleaned. I DID NOT use caned air.. bad bad bad. This is why.
Follow this link and see the pictures. The explanations under each one are very enlightening.
If you want to be equity as shocked, Google "lint in sewing machine" click on the pictures and take a look, nasty stuff.
I have a set of artist brushes and a fine round brush and have even used furry pipe cleaners, but never any canned air.
Also, IF your machine needs oil, only a drop or two and only in the spots that your manual tells you to put them, no where else. Oil in unnecessary places only attracts lint causing, well, what you saw above.
Moral of the story, well, clean more often, use better grade thread that doesn't make as much lint (long staple thread vs long staple thread) and have your machine serviced at least once a year and throw out that can of canned air!