Wind heavy thread on the bobbin either by hand or by machine. When winding by machine, wind without threading through any tension discs; give the thread a little tension by pinching it slightly as you slowly fill the bobbin.
Place the wound bobbin in its case as usual.
For threads thicker than regular-weight sewing threads, you'll need to loosen the tension in the bobbin case. Consider buying a second bobbin case just for this technique.
For removable bobbin cases, turn the spring screw in quarter turns to the left (counterclockwise) to loosen. Do this over a container to catch the tiny screw that may fall out if you loosen it too much. Loosen the tension until the thread pulls easily from the bobbin case. The type of stitch you use, as well as the weight of thread in the bobbin, will dictate how loose the tension should be.
If you have a drop-in bobbin case, consult your owner's manual for help with loosening its tension.
Choosing Stitches
Generally, use long stitches when using decorative threads; some threads are too coarse for close stitches and many threads look prettiest in long stitches. For machine-guided stitches, adjust the machine's stitch length and keep the feed dogs up. If you want to use programmed stitches, keep in mind you'll be more successful with stitch sequences that do not overlap and create bulk. To lengthen free-motion stitches, use a slower speed on your machine and/or move the quilt faster; feed dogs are lowered for free-motion quilting.
Experiment with stitches on a sample quilt sandwich and fine tune any bobbin tension adjustments. You may also need to adjust the tension for the top thread.
Getting Started
Since you will be quilting upside down, you'll need to layer the parts of your quilt in the order opposite to a traditional sandwich. Slightly stretch the quilt top right side down and pin or tape in place. Center and smooth the batting and the backing right side up. Baste the layers together.
With the right side of your quilt sandwich facing down, take one stitch and bring the needle up. Gently tug the top thread to bring the bobbin thread to the surface, pulling out a 6" tail of both top and bobbin threads. Quilt as you like. When you reach the end of a line of stitching, cut the threads, leaving a 6" tail. Secure the thread tails by threading them into a large-eyed needle, tying a knot and burying the knot and tails in the batting.
Have fun experimenting with threads and stitches to give your quilts a beautiful new look.
