I just posted this to my blog, but thought it might be of interest here, too:
I have now assembled nearly all the tools I need to start work on the Munsell color matching dye study group. So far all I’ve done is put together the Munsell Student Color Set – which asks you to arrange a bunch of chips by value, hue, and chroma – and document my methods. Unfortunately I needed quite a bit of equipment to really get started – pH meter, volumetric flasks, weighing boats, oh my! The last of it arrives today, so this weekend I will start work on my samples.
The first thing we are doing is working on our procedures and technique – dyeing one neutral color (because neutrals are combinations of multiple colors and thus the hardest to get right) three times in three separate dyebaths, to make sure we can reproduce the color reliably. First at 1% DOS (Depth of Shade is the ratio of dye to dyed goods – in this case, 1 gram of dye per 100 grams of yarn), which is a medium dark color, then (once that is repeatable) at .3% DOS, and finally at a very pale shade (.06% DOS if I recall correctly). That will be quite difficult and will involve a lot of tinkering with and/or hovering over dyepots – but is necessary. If you don’t have the process down pat, you won’t be able to reproduce colors precisely.
In my case I will also be testing out my buffer solution, which is currently citric acid buffered with soda ash. There are a number of reasons that Karren thinks it won’t work, so I will have to test it with a pH meter at various times during the dyeing to make sure it is holding the pH at precisely the right level.
Karren is having us work with great precision – measuring to +/- 2% accuracy in mixing up and dispensing dyes –and using techniques and tools more common in chemistry labs than in home dyeing. But I appreciate this kind of rigor – so different from the slapdash methods that typically get taught. I figure it’s better to learn how to do things precisely and with rigor, and then slack off later (within the limits of what produces acceptable results) – that way if I need precision, I have it available, and if I just need to slap something together, I can easily do that as well.
I expect to complete the first set of samples for process testing this weekend. Stay tuned for pix!