I own the Janome Artistic SD 18 longarm machine. I bought it new almost 10 years ago. I have had no problems. It has been a great machine and I always have a quilt under it's needle. There is a YouTube about tension by Jamie Wallen. He does not work on a Janome Artistic but he has great information on tension. Once I watched his session on tension, I watched it again. It was and has been a wealth of information. Also good idea to check your threading. That can make a world of difference. Even if you think it's right, check it again. I hope you have good luck with your machine. It has certainly been a good machine for me.