The first batch of indigo was a small trial batch on 15L because I heard so much about the difficulties with indigo and that it was supposedly a lot trickier than e.g. madder and onion skin. As a low volume trial, I only dyed some swatches and some left over yarn that I had lying around. In my previous entry I covered the basics of indigo dyeing, look it up here if you’re interested.
From the left it’s wool, silk, wool, wool, store bought yellow wool and grey wool. Everything turned out pretty uneven but it’s not realistic to expect perfect result on the first attempt. Besides, it’s indigo, you can always re-dye it for a more evenly dyed fibre.
Considering the instructions for indigo batches I always use Sandström and Sisefsky (1970) for this purpose. Since I don’t know the exact chemistry behind this process (!) I use a linear model to keep the same ratio in each batch. That is, I just multiply or divide the value in the existing instructions to fit the fixed variable. The fixed variable differs from time to time, sometimes I have a finite amount of indigo, sometimes I have a certain amount of yarn I want to dye and sometimes there is a volume limit on the cauldron I am using. This makes me re-calculate everything before dyeing but that’s not a bad thing because I like to have time to think things through, which is something that I am forced to do in such cases.
As you can see, I try to write down the date, mark the fixed variable and then write down the other amounts used so that I would be able to re-do the exact same thing if needed. In that way, it’s easier to say that a certain hue can be made or if I would need to dye some more fabric or yarn in a similar hue.
Concerning the chemistry of the dyeing process, I aim to get a better understanding of the chemistry in time but this is a work in progress. If I am able to do that I think that it is possible to do several process optimisations, which would result in the usage of less material and heat but still having good water and light fastness in the dyed material. Using a linear model is often a very simplified solution, many chemical processes are not well represented by a linear model and it is possible that it’s the same case with the indigo dyeing process. I’ll get back to you if I find anything worth sharing.
The larger piece of wool fabric that you see to the left in the first picture was later on used as a lining for a 14th century womens hood, which is a comfortable use of an uneven dyed fabric since most of it won’t be seen anyway. Tablet-woven edges done using yarn in the same light blue hue from the same batch, just to keep up with the latest reenactment fashion ☆
My hood is made from leftovers so it’s a little lacking at some points but if you want an excellent tutorial for this hood you should check out Katafalks tutorial here.
I still haven’t done anything with most of the yarn since I don’t have any reenactment related ideas, suggestions are welcome. Worst case scenario, it’ll be used for modern knitting.
Smaller batches are always useful for learning and also very easy to handle so I’d definitely recommend it as a good starting point. Developing a habit of writing things down will also make it easier to backtrack your work, to learn from it and to know what kind of colour you will get from a specific setup. Notes are a superior tool in order to communicate methods and results to others; also, you don’t need to remember everything if you have it written down. Overall, information exchange and feedback is fundamental for improvement and to avoid having everyone repeating the same mistakes.
Combine this with a sample set of each batch and you will be on your way to greatness. Now get a fancy notebook and get going.
Sandberg, Gösta & Sisefsky, Jan (1981). Växtfärgning. 5., [omarb.] uppl. Stockholm: Norstedt.