I have a small, cheap Singer ($100). The manual did not say anything about cleaning. After reading about cleaning on the board, I emailed Singer and in a few days got the response. It is supposed to be cleaned and oiled regularly, depending on us, - and they gave me the information on how to find the method to do that from another model. I now clean and oil about once every 3 months or so, depending on the use and waht I am sewing (flannel and fleece more often). The machine runs a lot quieter and smoother after the cleaning - which involved taking out the bobbin race and taking off the plate. Now if I could just remember to change the needle as often.