For the past couple years I've gotten increasingly into fiber arts. Last year, after not being able to reorder a specific hand-dyed roving I found on Etsy, I decided it might be worth dyeing myself. So I started researching all the ins-and-outs of dyeing my own fiber at home.
A lot of experimentation is required to get the results you want, taking copious notes so that you can repeat results is a great idea. This Instructable is a basic introduction to dyeing silks. It is not an exhaustive tutorial, but a way to get going. There are several other methods of dyeing silks, I just happen to really like immersion dyeing solid colors.
Step 1: BoM
Silk (for this Instructable I used silk noil)
Acid Dyes (I have a variety of Dharma, Jacquard, and ProChem dyes)
Scale (I have a scale for weighing fiber amounts and a more precise jewelers scale for weighing dyes)
Large jars (most of mine are recycled pickle or other condiment jars)
Roasting pan w/lid (Savers is a great place to find inexpensive tools)
Masking tape & markers (for labeling)
Coffee stirrers/stirring sticks
Rubber gloves, protective wear, goggles etc. The dye powers will stain your skin and be a pain to get off.
Step 2: Synthrapol Soak
All fiber has to be soaked before it can be dyed. Soaking allows the fibers to open up, making it easier to absorb dye. Silk can be hard to wet so the longer you let it soak, the more successful your dyeing will be. You want to follow the manufacturer instructions for Synthrapol or whatever textile detergent you use, but generally a drop or two of the solution is sufficient. Make sure you are using a container that can hold enough water to allow your silk to move freely.
If you don't have either product, dish washing soap can be substituted.
The silk noils shown here actually soaked in a Synthrapol bath for 4-5 days. Partially because I was also prepping soy silk at the same time and wanted to dye that first, and partially because I knew a longer soaking time wouldn't hurt.
Step 3: Dye Prep & Soak
How much dye powder you will need depends on how much fiber you are dyeing. I use this calculator to determine the percentage of dye powder I want per weight of the fiber. Dharma also has their own calculator that is tailored to their dyes.
Dharma recommends using between 1.5-2% of the weight of your fiber for the amount of dye powder and then mixing that powder with a cup of hot water to dissolve the powder (add liquid to powder, not the other way around). Add the mixture to your dye jar (assuming you aren't mixing in your dye jar) and then add your fiber. You may need to add more water to your jar to allow the silk to move around more freely. It ultimately doesn't matter how much additional water you add to your dye bath as the silk will absorb the dye, not the water.
Let the silk soak in the dye bath for at 12-24 hours. I've found this increases color intensity AND helps with exhausting the dye.
Step 4: Add Heat
After the 12-24 hour dye soak, add a couple of inches of water to your pan and slowly turn up the heat. Don't let the water go over 180 or get to a boil. Too much heat will cause the silk to lose luster. Keep the pan covered when you're not checking temps and water color. I tend to check every 10-15 minutes until the water starts to appear clear. The silk will absorb as much as the dye from the dye bath as it can. Some colors, will never fully exhaust no matter what you do (I've noticed this is particularly true with some blues, pinks, and blacks).
Step 5: Cool Down & Rinse
Once the dyes have all exhausted (or have exhausted as much as they're going to, some colors will not exhaust fully no matter what you do) remove the pan from heat, keeping it covered, allow everything to cool down overnight.
Before rinsing, you may want to add a drop of vinegar to each jar to help the silk restore it's ph levels. Let sit for another 5-10 minutes and then continue on to rinsing.
To rinse the silk, remove it from the dyebath (which will likely be very clear) and rinse under cool water until the water runs clear.
Step 6: Dry
Allow the silk to air dry before use. I have a couple 3-tier sweater drying racks that I put all my recently washed fibers on for drying. The thinner the fiber is spread, the faster it will dry.
The second picture is the soy silk I dyed. Except for the black, I didn't leave the other colors in their dyebath for 24 hours before adding heat. As a result, the colors did not take as well and in some cases, pretty much washed out completely.