At the end of every project I clean and oil my machine and replace the needle. With every bobbin change I also clean out any lint. If it's a big project, I'll oil it again somewhere in the middle and may change the needle. I'm a little picky I think, but my dealer is almost two hours away and a friend who has the same machine didn't do any routine maintenance and paid through the nose to get it back in shape. I also use a magnifying glass to see the needle tip and you can really see if the tip has rounded.