Even though this is an older thread, I am so glad it was bumped up to the top somewhere.
I've only changed my needles when they break. I've never done that because they were dull. I didn't realize that machine needles COULD get dull. They are at a point all the time. My machine has been making a thud thud sound the last two times I used it. I packed up early yesterday and was trying to figure out where to take it to get it fixed. I'M SO SILLY!!!
Oh, another question: How does one de-lint a machine. I tend to get lint all up into my presser foot. I use a 1/4" foot. So I have to take the foot off and wipe the shaft/ankle whatever area with a damp lint-free cloth. I do the same thing to the presser foot to get all the lint out. Is that what you were talking about??
Melissa