Monday, February 18, 2013

A bad dye job

Today I was working to turn this yarn
into colorways for a class I'm working on.

I suspect that I waited a little too long to add the acid on this teal batch and the dye hit quickly. I use glaubers salt as a leveler and there was a lot of it in this dye bath, but clearly I did something else wrong as you can see the unevenness before I even took it out of the bath.

So I am afraid I am going to have to go back to using some of these especially for my lightest colors.
I used to use all three at various points (Synthrapol, Abegal SET, and sodium acetate), but dropped them one at a time as things seemed to be going well. Perhaps I'm having trouble with the well water here and probably I should test the pH of it right off. Heaven only knows what else is in it as it frequently smells like sulfur (which is a nice addition to the frequent skunk smell around here especially this time of year--we measure the seasons by the skunk migrations now).

Synthrapol can act as a surfactant to improve the penetration of water and dye into wool. I always soak my fiber overnight but this doesn't seem to be enough for the lightest colors.  Glaubers salt is sodium sulfate and is used as a leveling agent which I do use in all of my dyeing below about a 3 depth of shade and with colors as light as this teal, I use it at 10% WOG.

Abegal SET is another leveling agent which helps create an even color by slowing the rate at which the dye molecules attach to the fiber as well as increasing dye penetration. Sodium Acetate is a pH buffer and my research suggests it helps keep the pH of the pot from drifting upward at the end of dyeing. I am not sure I need to return to using it as my pots seem to remain below pH 5.0 during the whole process.

It is also possible that the pot was too acidic for the light color which helped the dye hit quicker. I don't usually measure the pH of the dye pot very carefully. The citric acid I use takes it down to about 3.5 and so I just put in enough to do that. But maybe pH 3.5 is too low for these light colors.

At any rate, I will have to take more care with the lower depth of shade colors in the future and experiment with some of these assists for them. The colors at DOS 1.0 or more are quite even almost all of the time.


Alas, this teal yarn is going to need a do-over. Good thing I like dyeing.

3 comments:

  1. Trish at Tangled ThreadsFebruary 18, 2013 at 9:18 PM

    Bummer.

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  2. Rebecca,
    To me it looks like either too much acid and/or the dye bath was too hot when you added the dye.
    A pH of 4.5 is generally enough for Lanaset/Sebraset dyes. I add the acid in the beginning, before I add the yarn. For lighter shades, I add the dye at a lower temperature, between 100F and 110F. I then stir the yarn for about 1 minute continuously to take up most of the dye.

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  3. I think this is what happened Conni. I had the bath warming before I added the acid and it was likely too hot. And I am trying to dye in freezing temperatures and this is really messing things up for me. The next lot I did the dark black turned out gorgeously and the light light gray I messed up completely. I've never had two complete failures in a row in the dye studio. These acid wool dyes are so easy! ...but live and learn.

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