The single most important message we'd like to deliver in this article is that Power Scour Does NOT spontaneously cause your wool to felt. There's a large population of wool users that continue to tell wool newbies that it does cause felting. It's not based on any fact.
The fact is, Power Scour was originally developed and specially formulated for washing wool saddle blankets. The goal was to wash the dirt and/or poo out of the saddle blankets without causing damage to the natural fibers.
Technically stated: to solve the problem of dirty wool saddle blankets Unicorn Editions made a product with just the right concentration of active ingredients to optimally loosen soil and break-up organic contaminants while preserving the natural fiber cuticle and leaving no residue behind.
Note that ANYTHING can cause your wool to felt if it is mistreated while wet. Even water.
As long as you maintain a consistent water temperature (warm/tepid is best) during washing/rinsing AND keep friction to a minimum your wool knits should come out beautifully when washing with Unicorn Power Scour or Unicorn Beyond Clean.
To read more about Unicorn Editions visit them here.
What do we mean by keeping friction to a minimum or mistreating your wool?
Do not rub or scrub the wet wool. Instead use a gentle squeezing action where you press/squeeze the water out of the wool and then allow to relax and reabsorb the wash or rinse water.
Do not agitate. Instead soak and perform occasional squeezing to allow the wash/rinse to move through the fibers.
Do not apply the detergent directly to the fibers. Instead dilute the appropriate amount into the wash water before adding the wool.
Do not directly apply running water to the wool. Add wool to the pre-filled washtub to avoid the friction caused by the direct application of the water jet.
Do not temperature shock your wool. Wash AND rinse your wool in warm/tepid water (try to keep the temperature between washing and rinsing relatively consistent). Shocking the wool fibers by abruptly changing the water temperature can contribute to felting.
Warm or Tepid water is generally thought to be similar to the hand feel of baby bathwater temperature. My rule of thumb is that most wool knits do well if the water is between 30-35ºC. "Easy care" or "machine washable" wool knits are generally OK to wash at 35-40ºC. If my wool is particularly dirty I usually use water that is on the warmer side of the spectrum (35-40ºC), even non-easy care wool...just keep agitation low, low, low!
The second point I wanted to make about the Power Scour is that it is equivalent to the Beyond Clean. The ONLY difference is that the Beyond Clean is unscented. Power Scour has a mild lavender scent.
For whatever reason, I have heard people give new wool users the following advice, "Use Beyond Clean instead of Power Scour because it wont felt your wool"
It's half true. Beyond Clean wont felt your wool...but as I just mentioned, Power Scour wont either and the formula for each of these products is the SAME.
Take home message:
Unicorn Power Scour and Beyond Clean are great products for cleaning your wool knits. In particular, these two products work wonders on heavily lanolized, smelly or stained wool diaper covers. We actually use Beyond Clean and Beyond Soft to wash and soften all of our household laundry...including our cloth diapers. I highly recommend it!