Well, I tried some direct dyeing (paint then steam, a.k.a make a huge mess in the basement)
Some Finn top:
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and some 80/20 merino/silk:
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What you cannot see from my beauteous, carefully posed pictures, is I am STILL getting it fuzzed up around the edges - like a light surface felting. Maybe it's just compressed? I can't tell, don't have enough spinning knowhow.
and look at this insouciant little bit of Finn, previously kettle dyed pink:
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This one was worse, it feels pretty much unworkable now. Breaks my heart, as I adore that little red-orange-pink-yellow-green bit at the beginning.
It must be something with my rinse, then? But I don't know how in Howandaland that could be, as I'm letting temperatures change slowly, rinsing after they've cooled completely, in lukewarm water, and I'm just sliding it into the water. No agitation, no squeezing, no nothing. I drain and refill the rinse bath a few times (yes, never letting the water fall directly upon my precious, precious wool), then hang them up. That's it.
These appeared to come out of the steam rolls compressed - they didn't expand much in the water. So maybe it's something in the steaming while squeezed up in wrap? ARGGHH.
I've got something else to try, just layering the fiber in a container then baking. No rolling up in plastic wrap tubes. Maybe that'll tell me if it's the cooking-while-compressed that's the problem?