How to Vat Dye Cloth

Garment dying is a project I stumbled into while trying to find a very specific style of underwear I've been wanting and unable to find. I thought I might have found the underwear, but they were all white and I like colors. I used the fiber reactive dye and instructions from the Dharma Trading company, but I thought their instructions skipped around too much and decided to write my own, at least for doing exactly what I did.

The instructions mention using a washing machine, but I hand-stirred my way through it because I thought my roommates would flip out if they saw dye in the washing machine. I didn't even look into how well the washing machine works, because of this, though I imagine it's fine (it's not like professionals replace their washing machine between every batch of cloth). The instructions only address hand stirring.

Just a note up front: this isn't a short process. If you don't feel like stirring something constantly for nearly two hours, you might not want to do this. Also, I've noted on the shopping list which items will be stained. Lastly: this was done using the Dharma Fiber Reactive Procion Dyes and probably isn't relevant to other brands of dye.

Shopping List

A bucket, probably 5 gallons for a t-shirt (will be stained)
Plain salt (available in the grocery store, but look for a label saying it is iodine free or not iodized)
Calsolene oil (optional but I think it helped my attempt)
Soda ash
Fiber reactive dye (I used Burgundy)
Something to dye (certain fabrics work better than others. I used 95% cotton, 5% spandex.)
Very long wooden or plastic spoon, or large long dowel (will be stained)
Measuring cup and spoon set. In particular, 1 tsp., 1 tbsp., 1 cup, and 1/3 cup were needed for mine.
A smaller kitchen spoon or plastic spoon (any size).
A small to medium bowl or piece of tupperware (might stain).

Please note, I'm really not sure about the toxicity levels of any of this stuff. As such, I just used my craft measuring spoons, etc., which I never use on food. I think the utensils used for the salt and the soda ash would be okay, but the calsolene oil has some scary warning labels on it and I personally wasn't willing to use it on something I wanted to eat with later.

Figure out quantities

First, figure out how much water you're going to need to cover the cloth you're going to dye. You want plenty of water—it should be possible to stir the cloth without it leaving the water or touching the sides of the bucket. For my two pair of underwear, I used 1 gallon of water. For each gallon of water, you'll need the following:

1 cup salt
1/6 cup Soda Ash (for blacks, use 2x the amount of salt)
slightly under 1 tsp Calsolene Oil. It should be 2tsp per 3 gallons of water.

You'll also need to measure out the dye, and this can take a little weird math. Start with 1 tbsp of dye per 3 gallons. Check the color card on the Dharma website and see if there are any asterisks (*) by your chosen color. If there's one, double the amount of dye. If there's two, quadruple it. At this point, I had 2 tbsp of dye per 3 gallons (but I was only using 1 gallon). The amount of dye you end up with isn't an exact science, since you can reduce it for lighter shades or use more for darker shades anyway. I just filled my tablespoon about 2/3 full and called it good enough.

Prepare your cloth

If you bought what you are dying new, throw it in the washer once with your normal clothes. Don't use fabric softener, and don't put it in the dryer if you use dryer sheets.If you're dying an old piece of clothing, make sure it doesn't have any stains or leftover starch. In particular, grease stains are bad, since the finished piece will just look like it has a different sort of stain on it. Both stains and starch can usually be removed with hot water and harsh detergents, and since you're about to dye the clothing it doesn't matter if you discolor the stain area (as long as it doesn't have any grease left).

Start mixing things

Start by adding your chosen amount of water to your bucket, at slightly over room temperature. 16 cups is the same as a gallon (if you don't have a marked pitcher handy). Add the salt and stir well, until it fully dissolves. Add the Calsolene Oil.

Put the fiber reactive dye in the small bowl and add enough warm water to form a paste, while stirring it with the kitchen spoon. Slowly add more warm water, stirring as you go, until all dye is fully dissolved. Add the dye mixture to the tub, and stir it up with the big spoon or dowel until the coloring is even.

If you want to avoid staining, I'd wash the bowl and kitchen spoon as soon as possible.

Working with the cloth

Now, you add the cloth and stir it thoroughly. When stirring the cloth, the idea is to gently fold it over and around (not swish it in a circle). You want to be sure that no part of the cloth is left outside of the dye or exposed to a strong pocket of dye for too long. Also, I suspect some of the chemicals might sink to the bottom if left completely unstirred. This means that the entire time the cloth is in the dye, you'll be reaching over every 3 or 4 minutes to stir it a bit. Personally, I would grab a book and a kitchen timer, and set the timer for 5 minutes then stir for 1 minute before going back to reading. I think it's especially important to stir frequently for the first 5 or 10 minutes the cloth is in the dye, so maybe wait to start the book after that.

Stir the cloth in the dye for 20 minutes.

Adding Soda Ash

First, dissolve the soda ash in hot water in the bowl. Use the long spoon or dowel to push the cloth up against one side of the bucket. On the other side, pour in a bit of the soda ash mixture (maybe 1/6th of it). Stir the dye/soda water area for a moment with your stick then stir the cloth into it. Stir well to make sure some pocket of the soda ash water didn't get stuck in your cloth. Wait 2 or 3 minutes, then do this again. Over the course of 15 minutes, you need to slowly stir in all of the soda ash.

Lots more stirring

Go back to the cycle of stirring every 5 or 6 minutes (you can loosen up a bit the further along you go). For lighter colors, do this for 30 minutes. For really dark colors, like a deep purple, do it for 1 hour.

Removing the dye

There's a few ways to do this, depending on your setup, but you need to get the cloth out of the bucket and being rinsed, and empty the bucket. I put both in my bathtub, and let the water run over the bucket. This diluted the dye as it touched the tub, which seemed to help prevent staining. Don't leave any dye water sitting on a tub or sink for long, or it will leave faint stains. My underwear, which I dyed a deep burgundy, had to be rinsed a lot. I was at it something like 10 minutes. Once the water is running clear enough that you're okay with carrying it over your carpet, take it to the washing machine and throw it in for a rinse cycle.

Washing the fabric

Wash the cloth in the washing machine once by itself in hot water, so it can't bleed on anything. Come in and take a look during the rinse cycle. If it's not running clear, make sure you wash it on its own again the next time (this might happen with dark reds and blacks). Also, just like hair, the fabric might have lost some of its softness during dying. You might want to throw in plenty of fabric softener during the rinse, if the dye is running clear.

Timeline

Here's a quick timeline, to make keeping track of how long to do what easier.

Add water, salt, Calsoline oil, dye
Stir cloth for 20 minutes
Add soda ash over 15 minutes
Stir for 30 minutes on light colors, 1 hour on dark colors.
Rinse cloth, and put it through a rinse cycle in the washing machine
Wash once and check water for tint.
If clear, add fabric softener. If not clear, wash again then add fabric softener