I've been blogging on the steps of fleece preparation, so for pre-washing information (aka skirting the fleece), see here:
Now, on to washing ...
The easiest way is to send it to a fiber processor, and get back nicely prepared roving ready to spin. I've used Ohio Valley and Zeilinger's, both did a nice job.
Some people like to spin in the grease. This should only be done with clean fleeces that have been coated, otherwise the dirt and VM gets trapped in the yarn and cannot be washed out.
There are several ways to wash fleeces, to retain lanolin or not. One way said to be effective at removing dirt but retaining lanolin is to put the fleece in a bucket or tub of lukewarm water with alot of salt and let it sit overnight. I haven't tried this myself.
Here's what I do:
- Break the fleece into sweater bag sized pieces, and place them in laundry sweater bags. I only do 4 bags at a time, and they aren't stuffed full -- probably less than 2 pounds of raw wool.
- Fill up my top-loading washing machine (won't work with front loaders) with the hottest water and some Simply Green(R), Orvus, or your favorite wool scour; the dirtier the fleece, the more soap I use. Once it is full, I turn it off so it will not agitate. (Note: for really horrible fleeces I'll pre-soak without wool scour for an hour in lukewarm water.)
- Place the bags into the machine. Let them sit 30 minutes.
- Remove the bags and drain the machine.
- Repeat. If the water isn't draining clean, repeat as many times as needed so that it does.
- Then I do two rinses: first time, fill with the hottest water again, no soap. Put the bags in, let them sit 30 minutes. Remove the bags and drain the machine. If the water doesn't run clean (usually won't, the first time), repeat. If it doesn't run clean the second time, you didn't wash the fleece enough, and need to start over from the top.
- Once the fleece is clean and the machine is empty, I put the bags in the machine and set it on the spin cycle. Be very careful that your machine doesn't spray cold water in during the spin; some wash cycles will do that. This removes almost all the water from the clean fleece, letting it dry much more quickly.
Once the fleece is dry, you can use a flicker to open up the locks and spin them, or card the wool with hand carders or a drumcarder into roving or rolags. Combs can be used to make top, the preparation used for 'worsted', or compressed, smooth yarn.