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How To Make Cold Process Soap

Soap making from scratch really isn't that hard.  It does take a little time, patience, and preparation, but you end up with soap so wonderful you'll decide it's worth all the work.

I LOVE my handmade soap.  And I know you'll love yours too.  Are you ready to try it?  

Make sure you familiarize yourself with the process before starting out.  Also, read up on the process by checking out these posts:  

What Is Cold Process Soap?
Lye Questions and Answers
Lye Safety Rules 

This type of soap making takes time, and trying to rush through only leaves you feeling stressed, can lead to mistakes that ruin your soap, and definitely takes all the fun out of making soap.  (You are doing this for fun, right?)  Soap making is a great way to spend a lazy afternoon.  Give yourself several uninterrupted hours.

Safety Reminders:  Handle lye carefully.  Wear goggles and gloves.  Only use stainless steel or rubber/plastic implements (never aluminum).  And always add lye to the water... never the other way around.  (Make sure to check out the lye safety rules.)     

Necessary supplies:
(These should be used exclusively for soap making.)   
  • Stainless steel pot
  • 1 large plastic pitcher
  • Cups and bowls for measuring oil and lye
  • Plastic spoons or rubber spatulas
  • Cooking thermometer
  • Stick blender
  • Scale that weighs in pounds and ounces
  • Soap mold (this can be as elaborate as a wooden mold made just for soap, or as simple as a shoebox lined with wax paper)
  • Your cold process soap recipe 

Step 1: Gather all supplies and ingredients.  You'll want to have everything you'll need on hand and within easy reach.

I like to read through my recipe a time or two to make sure I'm familiar with it.  I also like to lay out all of my ingredients.  This has saved me quite a few times from forgetting to add an oil.    
 Step 2:  Measure out the water according to the recipe directions.  Remember, all cold process soap ingredients are measured by weight and not by volume (unless it's stated otherwise).

Put your water in the plastic pitcher, one large and sturdy enough to stand up to the hot lye solution.

Step 3:  Put on your goggles and rubber gloves.  It's time to weigh out the lye.  So long as you're careful with it, there's no need to worry.

In a steady stream, pour lye into water.  Stir until dissolved.  This solution will get really hot!

I like to set my pitcher in an ice water bath in the sink, because it helps reduce lye fumes and cools the lye water solution down much quicker.

 The lye solution will take a while to cool down.  I checked the temperature of my solution a few minutes after I added the lye.  It's still over 150 degrees. 

 Step 4: Weigh out each oil and put into the stainless steel pot.

Don't forget to take into account the weight of your container.  If your scale has a tare feature, place the container on the scale, turn it on, and your scale will be calibrated to zero.

Otherwise, measure the empty container, and subtract this weight from the weight of your oils to get the correct measurement. 

Once all of your oils are in the pot, warm them on very low heat until solid oils are just melted.  Don't over heat your oils.

When your oils are melted, you can take them off the heat.  They'll need to cool down, just like the lye solution.

Step 5: Let the lye water and oils cool down a bit.  You want both the lye solution and oils similar temperature, and between about 90 and 100 degrees.  (If the oils get too cool, you can warm them back up a bit.)

This cool down can take a while, so use this time to prepare your mold, measure out colorants and fragrance, and maybe have a cup of tea.

Step 6: When the oils and lye water are both about the same temperature, it's time to rock and roll!

Pour the lye solution directly into the pot with the oils.  (You are still wearing your rubber gloves and goggles, right?)  Grab your stick blender and start blending, scraping the sides of the pot every so often.

Step 7:  Keep blending until your soap starts to thicken (this is called trace in soap makers terms.)  It can take up to an hour or more to trace, but usually it happens within about 20 minutes.  Just be patient and keep blending.

 See how the color has changed in my soap pot?

Step 8:  My soap has traced!  It's nice and thick, almost like pudding.  Doesn't it look nice? 

Go ahead and add your fragrance, colorants, herbs, etc. as directed by your recipe.  Just give it a quick stir to make sure it's well incorporated.

Step 9: Pour your soap into the prepared mold.  At this point I had to put my camera down so that I could add my ingredients and pour, but here is my soap right after I poured.

My wooden mold comes with slats so I can make several different soaps at once.  You can do the same thing by measuring out individual bowls of your newly made base, coloring and fragrancing each, and pouring into separate molds.    

Step 10: Put a lid on your mold (I use a smooth sheet of plywood, but the lid can be as simple as a piece of cardboard).  Wrap your soap mold with an old towel or blanket, to keep the soap warm.  Here, you can see that I wrapped it in a blanket and added a few dish towels for good measure.  Your soap will continue to generate heat as it saponifies. 

That gooey mixture is going to firm up and turn into lovely soap.  Let it set undisturbed for 24 hours to do so.

Step 11: Now, for the exciting part.  Unwrap the blankets, remove the lid -- and unmold your soap!  I turn mine out onto a sheet of wax paper.  Admire it for a bit, then cut into bars.  It will be solid, but still soft, almost the consistency of cheese.

Step 12:  Undoubtedly, you're ready to use your soap, but you'll have to wait a bit longer.  The soap bars still need to cure.  Set them out of the way somewhere, uncovered, to cure for about 14-30 days.  Turn every few days or so, to expose all sides to air.  As the soap cures, it becomes harder and more mild.  After your soap has cured, it's ready to use!

Enjoy your handcrafted soap!  Aren't you ready to make another batch?

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