I have to smile when people talk about changing needles. I think I probably change more often than necessary, but it can avert a lot of problems. The local repairman is also a friend and he always puts a new needle in when he works on a machine. It adds 60 cents to the bill. One lady demanded to know why he put in a new needle when she had not authorized it. She told him that there was nothing wrong with the needle that in it and anytime it was little dull her husband would sharpen it for her. She had been using the same one for 20 years. He put the old needle back in and removed the 60 cents. Don't know how many more times it could be sharpened since the tip was nearly up to the eye.:)