Due to impatience to get on to the "good stuff", I knew I was damaging the gears in my pasta machine by forcing too hard or too thick through it. While kicking myself for doing that, I ran across this: http://desiredcreations.com/howTo_TLAdvPQueenMaint.htm
Desiree describes the workings of the pasta machine and how to take it apart to fix it. She made it look so easy, with step-by-step photos, that I decided to try it. Much to my amazement, it worked! I think on one of my machines the gears aren't meshing correctly, which I don't know how to fix (if it can be fixed), but it is much better. I lubricated everything well, then put them back together. And I didn't even have any leftover parts!
Thanks, Desiree, for the help. Now...back to the "good stuff"!