We recently had an afternoon workshop doing this in my local spinners' group, and it was great fun. The lady who taught us is still spinning Mule fibre she dyed this way in 2001! The beauty of the technique is that you put unwashed, raw fleece in, and you end up with dyed usable fleece that you can store for years if you want.
All you need is a roasting tin or similar that will fit on top of your stove or range, some vinegar, washing up liquid and acid dyes.
Here's what you do:
- Take a roasting other other suitable tin and put a little water in the bottom - maybe 1/2”.
- Add a really good glug of distilled vinegar and three good squirts of washing up liquid.
- Put on the heat - not too hot but not the lowest.
- Fill the roasting tin with whatever fibre you wish to dye - really cram it in. You can use any fibre but raw (unwashed) fleece is best. You can presoak it (just in cold water) if you want but you don't need to
- Add water until it just comes over the fleece when you press the fleece down.
- Sprinkle your acid dye colours across the top of the fleece. Use the powder dry and don’t worry about the upper surface of the fleece being dryish at the moment. Don’t put the dye everywhere - leave spaces for it to spread out. For a true rainbow dye, you’ll be using the primary colours, but you can use any colours you want, of course.
- Leave the pot heating - you want it to come up to a simmer fairly steadily, maybe over about 20 minutes.
- When the water is simmering, set the heat to maintain that state and put the timer on for 45 minutes.
- Take the pot off the heat and leave to cool until you can safely handle the fleece. Remember to wear rubber gloves! (I didn't - I had blue hands and one blue eyebrow for several days... )
- Lift the fleece out of the pot, let as much of the fluid drain back into the pan as you can.
- Thoroughly rinse the dyed fleece and spread out to dry.
- Take more fleece and repeat the dyeing process; you can add a bit more dye if you think it needs it or you can just let the fleece soak up the exhaust dye that’s there. (Which is environmentally friendly, as there is less dye chemical to discard at the end.)
- You can repeat the exhaust bath dyeing process but you will need a little more dye if you didn’t add any on the second round.
I'll be having a third day at this on Friday, I've charged the camera battery up and will try to take before, during and after pictures.