Acid vs iDye for wool
  • So, I have 8 yds of currently taupe tropical weight worsted wool suiting fabric that I want to make a dark smoke/charcoal gray... think hematite or gunmetal wire.

    I have two packets of iDye in Gunmetal, and I was thinking of putting it through a Color Remover treatment first, then dyeing.

    What I really want to know, though, is: Should I go extravagant, and try the Acid dyes, or can I use the iDyes (not having to worry about portioning would be nice) to make this work?

    aka LadySybyl
  • Hi Grace,

    While you can use the iDye for wool you will get more predictable results and in my opinion, a much easier time of it, with the Acid Dye. The process isn't that much different; stove top dye 'vat', adding vinegar, etc. With both methods you'll want to predissovle the dye, add it to a cool dye bath, add the prewetted fiber, and very slowly bring the temperature to a low to med simmer for approximately 15 - 30 minutes, allow to cool on its own, then rinse.
    The benefit of the Acid Dye over the iDye is that the Acid Dye is specifically designed for use with protein fibers (wool, silk, etc.) where as the iDye is developed for use with multiple fiber types and therefore will have some dye molecules which won't be interested in fixing to the wool. (Paula Burch discusses this at her site: in more detail - and with better science:)

  • Ok, so I'm reading her website, and it brings up a really good point: How lightfast will this be???

    My purpose in dyeing this fabric is to create a Renaissance Faire dress out of it, and I don't want this fading if I'm out of doors for a couple days....

  • There is a great chart at our web site that will give you information on Acid dye light and wash fastness. As a rule direct dyes will be less wash fast than Acid dyes but they are somewhat similar in light fastness.