A question I was asked is if it’s important to prewash hand dyed fabric before you quilt it.
There are several considerations in deciding if you want to add this step, including removing sizing, shrinkage, bleeding, hygiene, precut fabrics and the purpose of your end piece.
In the past manufacturers added sizing (starch) to commercially produced fabrics to mask poor quality fabric. It is my understanding that this practice has stopped in North America. However, fabrics are imported from many countries and it would be a good idea to check where it was made. ‘Hand dyed fabrics’ are usually made from pfd fabrics (prepared for dyeing) which means that no surface treatments were ever added to the fabric and what you see is what you get. I recommend buying the best quality fabric you can afford and sticking with new fabric, as opposed to possibly buying older fabric which may have undergone a sizing treatment.
Shrinkage occurs when you have a low thread count. Flannels, for example, are made from a very loosely woven fabric which is then brushed to create a soft feeling. If you are incorporating different types of fabrics in a quilt (flannel, cotton, silk, satin etc.), you should prewash them prior to piecing to know that the fabrics won’t be shrinking unevenly. Our fabric has a thread count of 220 threads per inch which is comparable with the highest quality batiks. It will not shrink once dyed as it has been washed 3 times.
Bleeding or running of dyes happens when dye hasn’t bonded to either fabric or water and is available to attach to another spot on your fabric when it gets wet again. (Water allows unattached dye to move around again). This dye is sitting between the threads of your fabric. Red and blue dyes are more likely to have excess dye sitting on the fabric as these dyes have a longer striking time than yellow dyes. Pastels are made with less dye initially so that it is less likely that bleeding will occur. Very dark fabrics are more likely to bleed. If you ever notice that your hands appear to have picked up a trace of dye when you handle a piece of fabric, you should definitely be prewashing - maybe more than once! You can test for colourfastness without prewashing by ironing the fabric with extreme steam to see if any colour moves onto your ironing board, but colour transfer can be subtle. Nobody should sell fabric to you with 100% guarantee that it will not bleed. With commercial and hand dyed fabrics, this is a possibility. In our case, we prewash all fabric at least 3 times in hot water with dye inhibitors to remove this excess dye.
Fabric store owners have advised me that a lot of sneezing occurs onto fabric! If this concerns you, just prewash your fabric.
Prior to all these lovely precut fabrics that make quilting faster, it was easier to prewash fabric. These precuts are all packaged in some sort of cellophane so they are clean when you open them. I don’t think that precuts were offered back in the day when sizing was added to fabrics. I think that prewashing them might affect the precisely cut edges, making them less exact for piecing. In most cases where you are using precuts you would only be using the fabric in the package, so the fabric would all be treated consistently so that if it shrunk it would do so evenly. If you are using precut flannel, you might want to piece it and then prewash it along with your backing so that it is all preshrunk before you quilt it. My practise when using precuts is to stick to consistent fabric types and brands and then prewash the top and back together before quilting them. We offer our overdyed selections in jelly rolls. They contain 2 pieces each of 15 colours.
Wallhangings are less likely to be washed than quilts will be. Cleaning usually amounts to a good vacuuming so that the above considerations are not as likely to matter as they would for quilts.
I hope that these suggestions help you to make an informed decision about prewashing hand dyed fabric before you quilt it. If you want to be sure, just prewash everything. It’s an extra step, but your time is also precious and who wants to have a problem after a quilt is made?
If you get tired of seeing this imprisoned man let me know - for now he represents an answer to my request for questions.
Keep those questions coming. Dyeing2helpyou@gmail.com.