OK, I admit. I NEVER prewash fabrics - Except ... OK, there are always exceptions, but for the most part - NO, I don't wash them. Now, for those exceptions.
You have probably read lots of articles that say not to wash your quilt in a washing machine - to lay it in a bathtub and soak it. Right, ain't gonna happen with my back. But, there is a TRICK to washing scraps, ANY sized yardage or a quilt in the washing machine.
It's easy to eliminate nearly all of the strings on yardage. Just clip off a little triangular section from each corner of fabrics before you wash them. Try about 1/2" or a little less. You'll still see a bit of fraying, but not enough to create bunches of knots.
DO NOT AGITATE... DO NOT AGITATE... DO NOT AGITATE
DO NOT AGITATE... DO NOT AGITATE... DO NOT AGITATE
*Use a very gentle soap like Orvus Soap. Orvus Soap contains so phosphates or chemicals that can damage your quilt. You can find Orvus Soap at your local quilt shop, or you can order it from me in smaller 8 fl oz containers.
I'm sure everyone has thrown raw edge fabric in the dryer and ended up with lots of knots and twisted fabrics. What a mess. Never mind trying to iron the fabric.
You might try laying the fabric on one of those folding racks - or even outside on the clothesline. (Many days in Houston, I must admit that it might take days to dry with all the humidity!). You can dry smaller scraps by ironing them (turn the steam off).
What I have noticed is that the tighter the weave of the fabric, the better they turn out in the dryer. Homespuns are a very loose weave (compared to batiks) and you can pretty much bet that the homespuns are going to shrink up in the dryer.
One time, after I completed arranging inherited squares into 25-patches in an intentional and complicated color-pattern on my design wall, I realized that the pre-cut 2-1/2-inch squares had not been washed; lots of bleeders; darks, reds, turquoises.
I had been making a T-shirt quilt, so I took the plain backs of the T-shirts that would have been thrown away, and transferred the 25-patch blocks to the T-shirt fabric, and pinned them on with basting/safety pins.
I ran these through a **DO NOT AGITATE** wash cycle (see above), and they all came out perfectly... and in their original order.
If you have lots of fat quarters or yardage in the SAME COLOR FAMILIES, use a safety-pin and pin three or four fat quarters together at the corners. Wash
them as a unit. Really cuts down on the wrinkles and twisting.
For larger cuts of fabric, pin the folded fabric in the corners and along the sides. I've pinned as many as eight layers... It can be difficult to pin through, but don't skimp on the safety pins. The more yardage... the larger the folded-over pieces need
to be... maybe as large as a beach towel or bath sheet.
Only pin the eight EDGES to keep the fabric from bunching and wrinkling;
the center will remain unpinned so that the water can still freely pass
through the fabric to remove dyes and chemicals. Fewer layers are
preferred, but 8-yard cuts will require more layers.