Clones are not all the same. My Simplex was a pain to clean up because the bobbin holder opens from the back like the older Singers. No problem getting it apart but I didn't know it had to go back kind of as a unit. I think there are some clones of the real old Singer 15s and some of the newer ones - it may depend on which they were copying. After it got back together it is ok. It will all depend on that particular machine. You want to look things over to make sure all parts are there - just like any other machine. Even then you will find that it needs TLC and that is when you find things out.