I had been having problems with the needle hitting something and the tension was messed up causing big loops of thread. I have discovered that you must use the appropriate bobbin. I had two different kinds and didn't know it. The bobbin that needs to be used in this machine is a slender one. I had purchased extra bobbins at the store not knowing that there was any difference. So note that the bobbin you need to use for this machine is "shorter" than an average bobbin. Once I changed the bobbin - my problems went away and I was able to adjust the tension solving my problems! I also do have my manual - so if anyone is in need of a copy let me know.