Dear Jan,
Sometimes thread will "ball up" in the bobbin area of my sewing machine. Normally, my Janome machine has such consistent tension. Can I do something to prevent this? -Anonymous

Dear Anonymous,
When thread snarls on the underside of your fabric, it's almost always the upper thread tension that needs attention. There are three very common reasons why the upper thread suddenly seems to go "haywire." First, if a sewing machine is threaded too quickly, it's possible to miss threading the take-up lever. The take-up lever is the silver hook that is threaded just before you bring the thread down to the needle. When the thread is not in the take-up lever, it's like there's no tension at all. Thoughtfully, Janome has added a "stopper" to prevent the thread from popping out of the take-up lever. Taking a little extra care to get the upper thread past the stopper and all the way into the take-up lever will insure good stitch quality.
When changing thread colors for Professional-Style Embroidery, Memory Craft Embroidery Model owners need to remember to lift the foot between colors. The "P" foot might look like it's up when the needle is in the highest position, however, if the foot is not lifted, the upper thread will not drop into the tension. When you begin embroidering, the thread will loop on the underside. Allowing the thread to continue to build up in the bobbin area can cause an "overload" situation.
Last, but not least; thread quality can dramatically affect your stitching. Poor quality thread will break more easily, create more lint in your machine, and can cause inconsistent tension. The little bit extra you pay for top quality thread will save you hours of frustration. By keeping these three simple tips in mind you will enjoy that wonderfully consistent Janome thread tension.