Using Black Fabric
 

I've been looking at the Pictures section and have seen some gorgeous quilts. One I'd like to try has blocks outlined with black fabric. Is pre-washing the dark fabric enough to keep it from running?

I think there's a product called synaprol. I will stand to be corrected as I'm probably wrong but I always pre-wash everything and also use the color catchers.

I have used Kona blacks on several quilts. I prewash the fabric, and I have had no problem with running.

I'm not sure about the bleeding issue. However, I want to recommend Michael Miller's Jet Black fabric if you want the truist (is that even a word?), richest, deepest black. The hand of the fabric is much nicer than Kona black (which I have also used), which is another benefit.

What I recommend is testing a small square of the black fabric first. Drop into a glass of water and leave for several hours to see if any dye bleeds into the water. After that, take the dampened fabric and rub it against any whites or light-colored fabrics that will be in the quilt to see if dye transfers that way (this type of dye transfer is called "crocking"). If the black fabric passes both tests, I wouldn't hesitate to use it without prewashing.

I do, however, always take the precaution of washing the finished quilt the first time with Synthrapol in the largest laundromat front-loader I can find. That takes care of any small bleeds from all of the fabrics in the quilt.

Thank you all for the advice! Greatly appreciated.

Michael miller black is a wonderful black. However, I strongly recommend washing this fabric before cutting. In my experienceS, it shrank over two inches in width.

Good to know, bearisgray! Thank you.

Keepsake Quilting has a wonderful Amish Black, that I love to use.

Shrinkage is greatest in a fabric that is washed on its own. Once it has been moderately quilted to batting, batting takes control of shrinkage. That is, batting will not allow the fabric to shrink more than the batting shrinks. This does not apply when quilting lines are far apart. For example, if quilting lines are 10" apart then a fabric could shrink 1/2" in those 10". I like to quilt closer than most (no more than 3" between quilting lines, and usually less) so fabric shrinkage has never been an issue for me.

I use black a LOT in my quilts. I don't prewash, and with a color catcher or two I don't have any trouble with dye runs. I'm not really positive that a color catcher is really necessary but it's an old habit; it's rare for me to catch any dye from black commercially dyed fabric these days ...