Dyeing for Color: Adventures in Historic Dyes: September 2013

Playing with Weld, Madder, and Woad...

As part of the upcoming dye class series at Great Western War, I'm going to be teaching a section on Viking Age Dyes. After doing some research into which dyes we could definitively document as having been used, we settled on weld, woad, and madder as the ones we would use for the class. My dye buddies and I had played with madder before, but never with weld or woad, so we decided this called for a day of experimentation! I was extremely pleased with the results we got.

My yarn from the day

I had limited string to work with, so I mostly stuck with single dyes. The green was created with a weld/woad exhaust over-dye. The madder had not been previously soaked, so we ended up with some very pretty oranges. Our next dye day, we plan on using the same madder root to create a new pot. This should give us red, but I guess we'll have to wait and see! You can see that the blue we achieved is closer to a cornflower than the color we get from indigo. We also noticed that the oxidation process occurred more slowly than with indigo. You could see the color start to change a little when you pulled it out, but really you needed to walk away from it and let the blue develop. Another surprise was the light green that the woad pot became.

Some of the blues and greens we achieved using woad and a weld with woad overdye

Aldgytha's skeins from the day-- they included silk, natural wool,
and some commercially dyed yellow wool.

These pictures give you a better idea of the range of colors we got that day. Aldgytha's skeins are in the bottom photo. She had both silks and wools, as well as some commercially dyed yellow wool. We were surprised to see that the silks were not taking the colors as deeply as the wools because everything we had heard said that silks take color really well. We also had some interesting experiences with the commercially dyed yellow wool. We pre-mordanted everything using alum, and during that process the yellow dye leached from the yarn giving the other skeins a slight base yellow. Who knew? She was was able to get some really striking greens using that yellow and the woad exhaust.

Flavia was able to do some actual teaching that day (as opposed to herding cats demo style) and it was ah-maze-ing! I got to set up the pots on my own after going through the directions step-by-step and taking notes. We cheated a little bit by using weld extract and powdered woad instead of using the leaves or setting up a fermentation vat, but there will be time to play with that at a later date.

Madder

The madder was pretty straightforward. As previously stated, this was a first soak for the madder, so the colors we got were more on the orange side. Soaking the madder root leaches out the yellows allowing the red to come through on a second pot. To leach out the yellow, soak the madder root for at least 24 hours in warm water. Use a knee high pantyhose to keep the root from getting tangled in your fiber. The ratio is about 1/2 gallon water to a 1 oz bag of root. To dye with this you simply bring it to a boil and then turn down to a simmer. If you are using wool, it should be mordanted with alum.

Madder pot simmering

Weld

We used a weld extract to create the pot that day. According to Flavia, extracts would have been used in period and were created by boiling down a dyepot to concentrate the dyestuff. The resulting goo was then spread out and dried. This would then be saved for later use, maybe adding a smidge of alum to the mixture.

Weld striking- this is a dye where
the color takes immediately.
Soaking longer does not add to the color gained.

To use the extract was extremely simple- we simply added it to a pot of boiling water. We ended up dyeing some skeins just with the extract, and got a yellow more on the goldenrod side. Then we added 3 tbsp of soda ash for 1 1/2 gallons of dye vat. It really brightened the yellow up!

The goldenrod color we got before we added the soda ash.

Weld after adding soda ash to the pot.

Woad

Of the three dyes we used that day, woad was the one that by far required the most thought. We used Su Grierson's book The Colour Cauldron as our reference text for setting up the vat. This was especially cool because she's the dyer who did most of the consultations with the archaeologists analyzing the extant Viking Age textiles and dyestuffs! If you will be dyeing with woad or indigo make sure you use dedicated pots and utensils- you don't want to end up corrupting your other dye pots! Any fibers should be water saturated-- this will open up the fibers and help the dye penetrate better. You'll want to leave fiber in the pot for at least 4 minutes, longer if you want a deeper color. (Don't leave it overnight, though because the thiox will eat your fiber!) You can also do more than one dip with the same fiber. Do not add more fiber than the vat will hold unconstrained. You can spread the dye by manipulating the fiber with your hands, but make sure you put gloves on first. If you are dying wool, make sure you don't agitate the fiber too vigorously because it will felt. Woad is a substantive dye, so it doesn't necessarily need mordanted fiber, but everything we used had been premordanted in alum.

Silk scarf dyed with woad after oxidizing
(The initial green can be seen below.)

The most important thing to remember when using either woad or indigo is to:

Dip- Dip your fiber
Rest- Let the fiber sit for at least 15 minutes before rinsing. This is key to the oxidation process-- especially with woad!
Rinse- Use clean warm water, you can also add a drop of orvious wash. This helps get rid of excess dye and avoid crocking.

Once the fiber has been rinsed, soak it in cold water overnight to help set the color.

Wool resting after being dyed with woad

You can see the wool beginning to turn blue under the scarf. The scarf
is still oxidizing- it has only been dyed with woad.

Vat Preparation

Start 1 gallon of water heating in a dye pot, but do not let it boil. We attached a candy thermometer so we could monitor the temperature.
Place the woad powder in a small dish and stir in a little water a time until you have a paste that's about the same consistency as toothpaste. Set this aside.

Creating the woad paste
In another container (We used an empty glass jar.) Dissolve 2 ounces of soda ash in boiling water, stirring to dissolve it.

Making the soda ash solution
Slowly add the paste to the soda ash solution and stir until mixed.

Adding the woad paste to the soda ash solution
This "whole mess," as Flavia called it, then is added to the dye pot. At this point turn the heat way down-- you can actually even take the pot of the stove. Turn the stove off if the vat temperature starts to go over 100 degrees F.

Adding the mixture to the dye pot
Now comes the chemistry fun! The woad vat needs to be deoxygenated, and 1 oz of thiox sprinkled over the top and left to sit is just the ticket. (Sodium dithionite works too, we substitute thiox because it is a tad safer.)
Now it's time for some patience. You leave the vat stand for 20 minutes as tempting as it may be to play with it! You should see some really neat foaming from the chemical reaction as the vat develops. :)

The woad vat developing...

After 20 minutes stir in 1 more oz of thiox, and let it sit for 10 more minutes before dyeing.

Stirring in the second batch of thiox- look how foamy it got!

Overdyeing

One of the fun things we tried was creating a green by overdyeing some of the yellow we got with the weld with a woad exhaust. It's important to overdye the lighter color rather than dying with woad and then weld because the blue will corrupt the yellow dyepot. You also want to use an exhaust so that you don't overwhelm the yellow. To create an exhaust scoop a cup of the dyebath and place in into another pot. Then dilute it slightly with water. We just played around until it looked like we were getting the color we wanted. I'd start out more diluted and then add more dye liquid if you would like it darker. We were rather surprised by how green the exhaust turned. Woad seems to have more of an underlying lime color than has been our experience with indigo.