I have 2 Brother machines and love them both. 1 I;ve had for 11 yrs and the other I've had 3yrs. Do you have the books that come with the machines? They have very good instructions on removing the bobbin and the bobbin caseing, that hold the bobbin. I get lint as threads under the casing and so I make it a point to clean and oil my machine about every 1-2 mos. depending on how often I use it. My newest Brother the 3 yr old, states it dosen't have to be oiled, but I don't agree with that and I oil mine with sewing machine oil.