What Can You Do With Leftover Soap?

Soap scraps have been piling up here at MacBath headquarters . I've got stacks of loaf ends, leftover soap batter that didn't quite fit in the mold, and bars that didn't stamp cleanly or acquired a small scratch - all perfectly good soap that smells great and will get you clean, but not up to the high aesthetic standards that I set for sale.  

So what's a soapmaster general to do? Aside from using them in my own shower, tossing small scraps in with my laundry, or placing multiple bits in a bag for travel or camping, there is another option to take leftover soap and make it into something completely new - hand milling.

Step 1: Grate, grate, grate. Are you tired? Too bad, keep grating.

Step 1: Grate, grate, grate. Are you tired? Too bad, keep grating.

So what the heck is hand-milling?

To make hand-milled soap, your base soap is reduced to small grated shavings that are melted down into a thick paste. Once the soap is melted, the soapmaker can add any scents, colors, oils, or other additives that they desire and re-mold the soap batter. There are some excellent benefits to putting your soap through the hand-milling process: it reduces the amount of moisture, resulting in a harder and longer lasting bar, and the second heating often results in a milder soap. Additionally, people who don't want to work with lye can still have the experience of soapmaking. And while cold process soap has a 6 week cure time, hand-milled soap can be used immediately (as long as the base soap was fully cured prior to grating.)

I took an early experimental batch of my Holmes soap (it had come out a little too hard to stamp cleanly) and began to grate. 

Yes sir, yes sir, three bags full.

Yes sir, yes sir, three bags full.

Many hours of grating later (and many grated knuckles), I had three gallon-sized ziploc bags full of deliciously scented goat's milk soap. After admiring my handiwork, I double bagged the soap for safety and inserted the bags into my crockpot and canner. I filled them with water and started boiling!


I boiled the soap bags for about an hour and a half until they were nice and mushy. Wearing heat proof gloves, I removed the bags and kneaded them until the soap inside was a smooth paste. (Alas, I have no photos of this step as my hands were full of hot soap).

Once thoroughly mushed, I opened each bag and added 4 teaspoons of almond meal to act as a natural exfoliant. After thoroughly kneading the soap a second time to evenly distribute the almond meal throughout the batter, I cut the corner off of the bags and piped the hot soap into my cylindrical molds. 

Several hours later, I unmolded the soap to reveal super scrubby goat's milk and almond meal soap scented with vanilla and rosewood. It's going to be perfect for getting the dirt off of my hands after a long day in the garden.

Finished Soap

It's quite a transformation from a disappointing, unstampable batch of Sherlock Holmes soap to a completely new, scrubby and exfoliating soap! It's harder, which means that it'll last longer, and milder as well. Plus I really enjoy the more rustic look. If you've wanted to get into soapmaking but have been wary of the lye, I highly recommend giving hand milling a try.