Cold Processed Biodiesel Glycerin Bar Soap Kit

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Soap Kit - ingredients

Your Knice-N-Clean soap kit should have come with everything shown here.

  • Safety Glasses
  • Rubber Gloves
  • Thermometer
  • Soap Mold Liner
  • Knice-N-Clean fatty Acid Mix
  • Sodium Based Biodiesel Glycerin
  • Sodium Hydroxide (NaOH)
  • Shipping Box

Warning: Sodium Hydroxide is a dangerous chemical and should be used with caution. Gloves and eye protection should always be worn whenever working with Sodium Hydroxide.

Note: Be sure you have followed the directions for building the shipping box soap mold or another suitable soap mold ready.

Soap Kit - Equipment

Additional items needed.

  • 3-5 Gallon Container for Mixing the Soap
  • Container to Mix the Caustic Solution
  • Mixing Utensils
  • Immersion Blender
  • Slab Cutter or Knife
  • Bar Cutter or Knife
  • 32oz Distilled Water
  • 3oz Scent (optional)

Note: All utensils and equipment should be stainless steel, glass, plastic or wood.


Soap Kit - Heat Glycerin

Place your glycerin in your soap making container and slowly heat the glycerin at medium heat until it reaches 170°F.

Note: Soap making container should be stainless steel, glass or ceramic.


Soap Kit - Add Fatty Acids

Add the fatty acid mixture and stir them into the glycerin.

Allow the fatty acids to melt into the glycerin while keeping the temprature between 170°F and 180°F.

Soap Kit - Melted Fatty Acids

Once the fatty acid have melted turn off the heat.

Soap Kit - Distilled water and lye

Before mixing the caustic solution be sure you are wearing your rubber gloves and glasses that came with your kit.

Measure 28oz - 30oz distilled water.

Note: Be sure to have vinegar on hand in case of any spilage of the caustic solution.

Note: Never use aluminium utensils or container when mixing the caustic solution.

Soap Kit - Add Lye to Distilled Water

Slowly add the lye that came with your kit into the distilled water while stirring.

Note: Allways add the lye to the distilled water never the other way around.

Soap Kit - Stir Caustic Solution

Stir until the lye is completely dissolved.

Note: Try not to breath the steam from the caustic solution as you stir.

Note: The caustic solution will be very hot.

Soap Kit - Stir Caustic Solution

Slowly add the caustic solution to the melted glycerin while stirring.

Soap Kit - Mix Soap

Mix until you notice trace.

An immersion blender greatly speed saponification and the soap will trace more quickly.

Trace is indicated by a thickening of the soap. A dribble of soap on top of the soap mixture will take a moment to mix back into the soap mixture.

Note: There may be a foam that forms on the top of the soap. You can use a slotted spoon to remove the foam. Put this into another small mold, it floats! The kids will love it!

Soap Kit - Add Scent

Slowly add 3oz of sent to the soap while stirring to encorporate the scent into the soap.

Soap Kit - Pour Soap

Pour the soap slowly and evenly into the prepared mold.

Soap Kit - Allow soap to harden

Allow the soap to harden for 8 to 10 hours.

Soap Kit - Unmold Soap

Unmold the soap and mark a grid on the soap.

Mark the soap lenghtwise. You should be able to get 4 3 3/8" logs.

Mark the soap widthwise at 3/4" to 1". You should be able to 10-12 bars per log.

Soap Kit - Cut Soap

Cut the slab into 3 3/8" logs.

Soap Kit - Cut Soap

Cut the logs into 3/4" or 1" bars.

Soap Kit - Stir Cure Soap

You should now have 48 - 52 bars of soap.

The soap will need to cure for 2 - 4 weeks or until it's no longer caustic hot. During this time the soap will also get harder as the excess water evaporates.

Note: Prior to using the soap it should be tested to ensure it is not caustic hot. This can be done with the battery test, pH strips or a pH meter.

Note: The battery test is a quick and easy way to test the soap. Simply touch the soap to your tongue. If it bites like a 9V battery the soap is still caustic hot and should be allowed more curing time.