The Secrets of How to Make Soap in a Slow Cooker

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Crock Pot Soap

Learn how to make soap in a slow cooker with our cold process recipe of water, lye, and fat. This recipe is great for making crock pot soap!

Learn How to Make Soap in a Slow Cooker

When I first started learning how to make soap, somewhere in the back of my mind was the question: how can I speed up the curing process? Normally in cold process soap making, it takes 4-6 weeks for the soap to fully cure. I’ve had a *few* batches that were ready in 2-3 weeks, but normally it takes longer. Then I found out about crock pot soap!

Basic Recipe for Crock Pot Soap

To start a good batch of crock pot soap, you don’t need to do anything special. That’s right, you can use any recipe for cold process soap. Crock pot soap is sometimes called the hot process, different from cold process because it is heated and cooked for a while. If you want to use my basic recipe, there are no adjustments that need to be made. Start with the same ingredients and supplies.



  1. Find an old crock pot that can be designated for soap making. Be sure it is large enough so the soap has space to boil without spilling over. Many crock pots only have heating elements on the sides and not on the bottom, in which case you may need to double or triple this recipe to fill the slow cooker a little more.
  2. Pour the water into a quart canning jar. Slowly add the lye and stir until dissolved. Remember to wear long sleeves, use gloves, and wear a mask. The fumes that come from the lye will stop within a minute or so. (Read our response to the common question: Can You Make Soap Without Lye (Sodium Hydroxide)?)
  3. Next, measure your oils for your crock pot soap and place them in the crock pot. Be sure to measure them while in liquid form, not solid.  When the oils are hot (you can start on high to get it going, but then switch to low) you can add the lye. That’s right, I didn’t tell you what temperature they should be, because it really doesn’t matter with this process. If the oils are hot, the lye will be too and you’re going to cook it anyway.
  4. Once you get the lye and oil mixed together, stir by hand for 5 minutes. I honestly believe that this is very important as it brings all of the lye in contact with all of the oil. After 5 minutes, then use a stick blender to bring it to a light traceA light trace is more like pancake batter. Thick, but not like pudding. (This is different from cold process soap, in which the desired medium trace will look much like thick vanilla pudding.)
  5. Once it gets to a light trace, cover it and walk away. DON’T STIR IT! This was just about the hardest thing for me since I worry about it sticking. It won’t. After about 20 minutes, sometimes sooner, you’ll see some bubbling on the sides. Then it will start to boil (sort of) and turn translucent, almost like petroleum jelly. After approximately another 20 minutes, it will expand more and start to curl in on itself. You still don’t want to stir it yet. When it’s all translucent and has folded in enough to fill in the middle, then it’s done for now.

The Secret

This is the point where most instructions on crock pot soap tell you to add your herbs and oils and pour it, but you can’t, because it’s all ropy, hard, and chunky. This is where my secret comes in.

Turn Off the Heat

  1. At this point, turn the heat off. Then add about ¼ cup water and mix it in. It’ll take some work, but it will eventually start to smooth out. (If you want to add powdered goat’s milk, mix about 2-3 tablespoons with about 2 tablespoons of oil [yes, oil, not water – water makes it lumpy] and add it before the water. The soap will probably turn orange or yellow and get really pasty, but adding the water after that will loosen it up.) You can add up to ½ cup water per batch and still get good results. If you add more than that, it will be easy to pour, but then your soap will be spongy and won’t set up properly.
  2. After it gets smoothed out, then you can add dried herbs and essential oils to make it what you want. Pour it into molds, cover with wax paper, and let it sit for 24 hours. Don’t worry about retaining the heat. You just cooked it all out!
  3. After 24 hours, take the crock pot soap out of the molds. (Cut it into bars if needed.) Set it on some parchment or wax paper to cure for a week or so and that’s it. The 4-6 weeks have been reduced to a week by cooking the lye out and speeding up the oxidization process. Sometimes it takes another week, but most of the time the soap is ready within a week.


Just one more note: Be sure to use an old crock pot. The lye will eventually etch the ceramic and it can break after a few years. Of course, I use mine a lot, so most should last longer. And for clean-up, let everything cool and then add hot water and let it soak overnight. I use this water for my dishes or laundry. Rinse it and it’s good to go.

Have you ever made crock pot soap? If so, how did it go?


photo credit to heart hands home

About Debra Maslowski

Debra is a master gardener, a certified herbalist, a natural living instructor, and more. She taught Matt and Betsy how to make soap so they decided to bring her on as a staff writer! Debra recently started an organic herb farm in the mountains of Western North Carolina. You can even purchase her handmade products on Amazon!

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  1. Lisa says


    Thank you for this awesome idea. I can’t wait to try it!

    I have a couple of questions.

    I’m assuming this changes the properties of the ingredients since it is the heat process method? Can you substitute hard butters for the oils? Is the heat transfer method possible for this? I’m a newbie to cold process but not MP so I apologize for all of the questions.



  2. Mouse says

    There are so many pop-ups on this page that by the time I got done scrolling through all the ads I didn’t care anymore.

  3. Victoria says

    Help! I have made cold process soap using vegetable oils for many years. I tried the crock pot method. I measured using a scale and used a soap calculator. The soap cooked about an hour or so, and set up as pictured. Last night I cut it, and today I wrapped the bars in tissue paper. I did the zap test, and no zap. I then, just to see, tried a Ph strip. The strip showed high alkaline. I am sure if I age it, it should be fine, but, what did i do wrong?

  4. Katura Carter says

    I have a question. What size slow cooker did you use for this recipe? 5qt, 7qt? I’d really like to know so my first batch doesn’t end up a disaster. Also, after I finish the first batch, can I clean up immediately and start on another batch the same day without waiting overnight?

    • Debra Maslowski says

      The size of the crock pot only matters if you’re making larger batches Katura. I like to use my 8 quart with a triple size batch. It has a removable crock which makes clean up easier. Two things to remember-first, most crock pots only have heating elements on the sides so as not to damage the counter top when cooking. Smaller batches of soap may not go up high enough in the pot to properly cook. Then second, be very careful of overflows. I had my liquid soap overflow the pot and it damaged the cord. I didn’t know the lye had eaten through the plastic until I got zapped while cleaning it. Best course of action there is to unplug it before cleaning!

      • Katura Carter says

        Thank you for the response! How many bars of soap will this batch be if I used a standard soap mold? This will be my first time doing this and I’d like to not have anything left over. 🙂

        Also, can I clean up immediately and start on another batch?

  5. brittany says

    The step when or if you decide to add goats milk what kind of oil do you mix with it? does it matter or can it be any kind of oil?

    • Debra Maslowski says

      It can really be any kind of oil Brittany. I try not to use a solid oil, like coconut, because if the soap is cooler than the melted oil, it may solidify back on contact. Some of my favorites are sunflower and safflower for the vitamin E content and grape seed for the antioxidants.

  6. Misty says

    Ok, this will be my first time ever making soap of any kind. I’m wondering why the emulsion blender isn’t used at the end to blend it all back up instead of hand mixing with water? I’m sorry if this is a repeat question.

    • Debra Maslowski says

      No worries about repeat questions Misty. I’ll take them all! I don’t use a stick blender at the end because the mixture is so thick that the blender wouldn’t get through it. If you add more water, it may work, but then there will be a lot of shrinkage in your soap later. You can try it if your soap seems thin enough, just be careful not to make a lot of suds as you work it.

  7. Sheryl Brazier says

    I read somewhere to spray the molds before pouring the soap. I was curious to know what do you use to spray them with

    • Debra Maslowski says

      I don’t usually spray my molds, Sheryl, unless they have intricate designs. Then I use a spray on oil. You can get it at the grocery store, or you can buy a mister and use any oil in it. I use olive oil since it’s already in the recipe. After spraying, tap the mold a few times to get rid of any bubbles. If there’s too much oil and it leaks, just dab it with a paper towel.

  8. Audrey says

    My crock pot soap turned out orangish-brown. Is this normal? Will it possibly lighten after it is finished? If not, would you know what I did incorrectly?


    • Debra Maslowski says

      Without seeing it Audrey, I can’t say for sure what might have happened. If you used powdered milk, milk will sometimes turn orange or brownish as the sugars heat and caramelize. This is totally normal. It doesn’t happen every time, just sometimes. It may have to do with the heat, I’m not sure. If you didn’t add milk, it could have to do with the oils used. Some oils turn the soap darker than others. Usually, the color will fade over time.

    • Debra Maslowski says

      The coconut is used as a base oil, Nirit, not as a butter. Coconut butter is a different thing, not at all like shea or cocoa butter. You can use cocoa or shea butter as an added moisturizer. Add it at the same time as the essential or fragrance oils. Because the soap is hot at this time, you don’t need to melt it first. A few tablespoons should be fine.

    • JC says

      yep! get a big stainless steel pot, put your fat & rain water in, add the lye and stir as often as you can (yes it will be hard, but slowly softens & gets easier, keep stirring to incorporate fat with lye & water) for 48 hours. Wearing all the protection garb of course. Goggles, gloves, long sleeve shirt, face mask or bandanna to cover mouth & nose. Lye is dangerous!

      Only use a wood spoon for stirring. A really long spoon is ideal.

      At the end of 48 hours, heat on low to melt completely, add any “smelly’s” you desire and pour into a greased or wet cheese cloth mold, leave it to sit till hard, 24 hours or longer. Cut & wait for six weeks to cure some place out of the way. Lightly covered with a cloth to keep dust off.

      Lard or tallow are highly recommended for this recipe.

      Crisco, before it was made from soy & other nasties was my best soap fat. The bleaching and such are not favorable to put on ones skin though.

      Regarding lye. If your Publix grocery store still sells Red Devil Lye, go to a register and get a plastic bag. Use the bag as your glove to pick up can of lye and wrap in the bag. Remind the cashier to not touch the can or they will be itching & burning just from touching the can. Then I have cashier put in paper bag. Keep the can in the bags till ready to use. Use rubber gloves to handle can of lye while making soap.

      EXTREME CAUTION always with lye. goggles. gloves. face mask. long sleeves. Did I say Lye is dangerous? NO CHILDREN OR PETS around soap making or this lye!

      5 lbs fat
      1 (13 oz) can red devil lye (no blue crystals!)
      6 quarts cold water (distilled, rain, spring or well)
      3 TBSP borax
      Mix all as mentioned above.

      On molds~ I have used pvc pipe, cardboard box, shoe box, glass square pan, bread pan lined with freezer wrap (not ideal). Sky is the limit. Get creative.

  9. JC says

    for the newbies to soap making..if the batch fails, shred it and do laundry. A little goes a long way, so be careful. It is never a loss. Don’t toss. It can always do something useful~ be creative!

  10. Nerissa says

    Thank you for posting this, I’m excited to try your recipe this week…one question when you recommend using the emersion blender…once its used on soap can I use it on food again?

  11. Kathleen says

    I tried this recipe as my first attempt at soap making, but I didn’t fair too well. It came out spongey as was stated if too much water was added. The only problem I had was that I kept letting it set in the crockpot (NOT stirring) but then when I started the stirring process it acme REALLY stiff and I couldn’t work it out without more water.
    Is there a way to salvage this recipe and make it a liquid soap, and try the recipe again? Maybe my crockpot was running too hot? Mine is an OLD one from the ’80’s that has a BASE heating element. Not the drop in kind that is all you find now.
    Any help would be appreciated. I hate to waste that much material.
    Thank you,

  12. Tammy says

    Made my first batch of crock pot soap tonight, and have I got a beginner’s tale to tell…
    I used an old 6-quart crock pot and a total of 3 lbs. of oil (half rendered bacon grease and half coconut oil). A word to the wise: NEVER make soap in a 6-qt. crock pot using 3 lbs. of oil. I think it is going to be okay once it has cooled off, but I am sure that the final consistency was a considerably different than it should have been.
    I had to rescue the soap from spilling out over the lip of the pot. This eventually entailed taking the lid off because the mixture had bubbled up so high that it was lifting one edge of the lid up and pouring out that side, but the weight of the lid was not allowing the soap to go through it’s rolling motion in the rest of the pot. I ended up cooking it about twice as long as recommended because, after having taken the lid off, it just didn’t seem to be doing what it was supposed to do.
    There was no pouring of this soap even after adding the maximum amount of water and goodly amount of rosemary EO. I scooped it out and spread it into the molds. It reminded me of a cross between mashed potatoes and super thick fudge. Something tells me that this soap will be ready for use in considerably less than a week.

    • Tammy says

      Update: The soap is a little softer than my cold process soaps have been, but other than that, it is fine. Lathers nicely and leaves us feeling clean. It smells a little odd, but I think that is from the bacon grease. I think I’ll keep it in cold storage. There is probably enough there to last us a year, though I expect a few male family members may be getting some as gifts this year. It will be perfect for those outdoor-loving guys who are so hard to buy for!

  13. Nadia says

    Hi there – I have never made soap before, but I am an avid crock-pot user. The only “personal care” item I have made is deodorant…so making soap is a big step! 🙂

    My question is really about the crockpot. You mention that the lye will be hard on the crock pot. Does that mean I shouldn’t use my crockpot for cooking foods if I decide to use it to make soap? In other words, should I have a separate crock pot for making soap? (this might mean I go shopping for a new crockpot for food…)

    Many thanks in advance for your answer.

  14. Holly Fearnow says

    I just cooked up a batch last night. I used EVOO instead of regular olive oil because that’s what i had on handl. It almost seems a bit to oily, but then again it was my very first time making soap. As the bars cure, do they get less oily? Or is it because i used EVOO instead of regular olive oil?

    • Debra Maslowski says

      Usually the bards just harden more, Holly, but they don’t get less oily. It may have been the type of oil. I only use the cheaper olive oil because it’s not for cooking and it doesn’t need to be that pure. The soap just seems to turn out better. One common problem with this recipe is that people are afraid of the lye and tend to not fill the measuring cup all the way, or they use the wrong type of measuring cup. You need to use a dry measuring cup, not one meant for liquids. Either way, it looks like you had too much oil and/or not enough lye. There’s nothing you can do now to change it. I would let it sit a week or so and if nothing else, dissolve it in a bucket of warm water and use it to get rid of pests on your plants. I use a tablespoon or so in a spray bottle of water and mix it well. Then go spray it on aphids or spider mites. It will eventually start to smell rancid due to the excess oil. That’s when it’s time to get rid of it. Well diluted, it can be dumped down the drain.

  15. DeAnne says

    I too am wondering how much essential oil must go in to be able to smell it later. Never made soap before – what do you use as a mold?

    • Debra Maslowski says

      Hi De Anne! Another tricky question about the molds. You can use just about any kind of plastic as long as it has some give. I started with plastic shoe boxes. It made a large bar that would be cut after the first 23 hours. Then I went to smaller molds, but they lost the heat too quickly. I solved this by layering them in a cooler with sheets of cardboard in between. One client wanted round bars, so I made molds with PVC tubes. Use the thin wall, it’s easier to work with. Now I use almost anything I can find. Yogurt containers are my new favorite.

  16. joni says

    I was wondering about the ratio for adding dried herbs and/or essential oils? can I add as I like or is there a measurement I should try to follow in order to get a nice mix?

    • Debra Maslowski says

      There’s no good way to measure the amount of herbs and oils, Joni. You have to start slow and add more if you like. I’ve made the mistake of adding too much plant material and not having enough soap around it. It crumbles and falls apart. The oils are another thing you have to do by choice. I wouldn’t go over 5% of the total volume. I once dumped a half a bottle of peppermint oil in my soap accidentally. It was nearly unusable for the oil leaching out of it!

      • brittany says

        Hi Debra,
        I want to make soap with using peppermint essential oil…what herb would you recommend with this? I definitely like a little texture in my soap?

  17. Darinka says

    Great recipe Debra, thank you. Question, have you ever tried adding a hydrosol at the end instead of the water?
    I’ve done this with a few batches and it’s wonderful because it adds even more benefits to the soap not to mention added aroma. I’ve done Rose, Neroli and Lavender. I am about to make a Neem, Carrot & Goat milk recipe and I am hoping by adding neroli and rosemary water, it will help mask the smell even further. Wish me luck.

    • Debra Maslowski says

      Thanks Darinka! I’d nearly forgotten about hydrosols. Yes, I have used them, though they tend to lose some scent and color. I love rose water, and even though the lye seems to destroy the scent and color, the wonderful skin softening ability is still there. I’ve also used infused oils, like calendula, as part of the oil used. It works great this way too.

  18. Nita says

    I have never done cold or hot. But so want to try this!! Where do I get the herbs to put into my soap? and can a newby do this? Thanks

    • Debra Maslowski says

      Hi Nita, yes, this is geared towards newbies in the soap making world. I’ve made the instructions very easy so anyone can do it. I get most of my herbs from my garden. I always dry them first as the lye can rot fresh plant material and they can also add too much moisture. You can buy dried herbs at the grocery store (go for the bulk section as they are generally fresher there), a local food co-op or online. When I can’t get something locally or I need a lot, I go to reputable sources online such as Brambleberry or Majestic Mountain Sage.

  19. Natalie says

    Thanks for sharing your tips and a great recipe! I love the simplicity of this and want to attempt soap-making. Do you think it would work if I used rice bran oil instead of olive oil (allergic) and used the same exact amounts of it and everything else? I have read that rice bran oil can be substituted for olive oil, I just don’t know if it changes anything in the recipe.

    • Debra Maslowski says

      Hi Natalie, Yes, you can but the quality of the soap may differ due to fatty acid chains, lipids and so forth. The SAP value is very near the same, so the amount of lye you use wouldn’t change. Your soap may be harder or softer, so you may need to experiment. There is a great SAP chart at From Nature With Love.

  20. Phallin @ CottageHomestead says

    I was wondering if the same measurements consist for the lye if you use the lye beads instead of flakes? Also when you add the water at the end, what do you mix it in with….the stick blender or just a spoon? Thank you!

    • Debra Maslowski says

      I’m not sure where you are from, Phallin, but around here all the lye I’ve seen is in beads. Or possibly powdered. The flakes are usually potassium hydroxide, which is used for making liquid soaps. They are NOT interchangeable. If you are sure you have 100% sodium hydroxide, then I would weigh it and use a recipe that calls for weights. Then you can be sure you’ll have the right amount.
      As for adding the water at the end, I use a spoon. It’s usually too thick to get a stick blender into. It takes a bit to get it worked in, but it’s well worth it.

  21. Judy says

    Hi Debra,
    I am brand new to soap making. I want to try your recipe for making soap in the crock pot but I know I will want to add some essential oil for fragrance. Since this will be my very first time to make soap can you tell me how much essential oil is needed so it’s noticeable?

    • Debra Maslowski says

      This is always the hardest question to answer, Judy. It depends a lot on your nose, what kind of oil, the strength of the oil and the quality. I generally say start with 10 drops or so and add from there. Be sure to sniff coffee in between whiffs to clear out your sinuses. And remember, you can always add more, but once it’s in there, you can’t take it out!

  22. Darcy says

    Could you just put in goat milk instead of water and the powdered goat milk? I’m assuming that just like with other soap making that you want a crock pot and other utensils just for soap making and not used with food, right?

    • P J Kielberg-McClenahan says

      I hope we are talking about the same thing. “Melt and Pour” refers to soap made with meltable soap bases made of either glycerin, goat’s milk, castile soap, or olive oil based soap. No lye is required with the above soap bases, all that is needed is fragrance, color, emollients and any additive such as spices or oatmeal, etc.

      The cold-frame method requires lye, etc., and either requires a long “curing” time or the newer crock-pot method, as mentioned above.

      I have posted this to just make sure anyone reading understands about the methods, and that each one should be from a recipe especially tailored to the products being used.

      • P J Kielberg-McClenahan says

        Also, I get my “melt-and-pour” soap bases from Glory Bee Foods. They have a wonderful website with all natural products perfect for this type of soap making. Their prices are the most reasonable I have found, also.

        • Debra Maslowski says

          Thanks for clarifying that P J. Glycerin soap, or melt and pour, is an end product of cold or hot process. You need to add alcohol and sugar to clarify it and I’ve never been successful at that. I buy from great sources like Glory bee, Brambleberry or others that have it already done.

    • Debra Maslowski says

      If you’re making cold process soap, Darcy, you can start with goat’s milk, but it’s a long and involved process. I’m still working on perfecting it, so I can’t really give advise there until I do. That’s why I use the powdered milk at the trace, or add it to the melt and pour soap. Or, even easier, get the melt and pour base that has it already in it.

  23. Sandy says

    hi 🙂
    I’ve been wanting to make my own soap but haven’t yet, This recipe looks like it’s easy and not scary. I want to try it out next weekend. I would like to make an oatmeal soap, as I have skin issues and oatmeal is soothing, how would you recommend tweaking the recipe to use it and still make it work? I saw your comment above but it didn’t say how much to add.
    thanks for any advice you can give!

    • P J Kielberg-McClenahan says

      I have made castile melt-and-pour soap with the addition of oatmeal, powdered ginger spice, and pure lanolin (available from Lorann Oils in 1 lb. jars) that is soothing to sensitive skin. The ginger spice gives it a slight fragrance, and the lanolin and oatmeal adds comfort and moisture to sensitive skin.

  24. Ellie says

    Can powdered lye be used to make soap? I can’t find anything else and I’m not sure if I should use it.

    • Tammy says

      Yes, lye comes in powdered/crystalized form. The important thing is that it is 100% sodium hydroxide.

  25. Jill says

    Thanks for these great tips! I want to add that each oil and fat requires a different amount of lye. Always use a lye calculator to ensure that your soap doesn’t turn out too caustic. Oils cannot be substituted for each other without adjusting the amount of lye accordingly. has an easy, free online calculator. Planning for 5 or 6 percent superfat will ensure some degree of moisturizing qualities and give you that little “cushion” of knowing that no lye remains in the soap once it’s processed.

  26. Rhoda Edwards says

    This soap recipe looks so simple that I am going to try it out. I have a fear about soap making, not of burning myself but of not getting the ingredients correct to cause the soap to form. Thanks for the cup measurement it makes it so much easier, and many thanks for the recipe.

  27. P J Kielberg-McClenahan says

    I have been using a crock pot for making glycerin, castile or goat’s milk melt and pour soap for some time. It works great for this type of soap-making.

    WARNING: If you are making lye soap, use a wooden spoon ONLY and DO NOT USE an aluminum crock pot! Lye, aluminum and water can create hydrogen gas, very flammable and dangerous! Only use ceramic or stoneware.

    • Debra Maslowski says

      Thanks for the info P J! I didn’t know they made aluminum crock pots, but yes, you should avoid them at all costs. I’ve never made a good batch of glycerin soap, but intend to try it now. And then next on my list is liquid soaps. I just got some potassium hydroxide and I’m itching to try it.

      • P J Kielberg-McClenahan says


        My aluminum crock pot was purchased several decades ago, probably most of them have been discarded by now. I have used it occasionally, but purchased a larger ceramic slow cooker and retired the aluminum one, until I tried it out as a melt-and-pour soap warmer. Glycerin soaps are very easy to create; you can add emollients, colors and scent, and have a wonderful product. Just be sure to wrap it up tightly, to preserve the fragrance.

  28. Mary says

    I make hot process in a crock pot when I make soap. I don’t have the patients to wait the 4-6 weeks to use it, that’s why I chose the hp method. I’m fairly new to soap making (since last July(2013)). My soap has always turned out well, but I couldn’t get it to look pretty like the cold process often does. Someone suggested I stop the cook at the gel stage. Well, I zap tested at that stage, and guess what? NO ZAP! It’s still not super easy decorate, but easier than before. Your right, it does take longer before you SHOULD use it (pretty moist) but you CAN use it if it passes the zap test. Just is a softer bar than if you let it cure longer.

    • Debra Maslowski says

      Thanks Mary! I’ve never heard of what I did called the “ZAP” test, but it makes sense. People at my classes invariably freak out when I do it, but I remind them that it’s safe and show them my tongue. It still looks the same as it did years ago.

    • Debra Maslowski says

      Sure you can Leriec, Just be sure to check one of the SAP charts to see what it’s closest to. Then you’ll be able to figure out how much to substitute for another oil.

  29. Tammy says

    At the end you mention that sometimes it takes an extra week, but that it’s usually ready within a week. I am brand new to soap making – with two batches of cold process less than a week into the curing stage. So, how does one *know* when the soap is ready to use?

    • Debra Maslowski says

      That’s easy Tammy! Just lick it! Ok, not literally, but touch the tip of your tongue to it. If it just tastes like soap, it’s ready. If there is a slight sting on your tongue, it’s not yet. I’ve been doing this since 1995 and my tongue is fine, though I really dislike the taste of soap. I keep water nearby to get rid of that taste.

      • Debra Maslowski says

        Yes, that’s true. All soap is made with lye. There is no substitute. If you are careful, you don’t need to b fear it. I did for a long time, but I got over it. I still get burns on occasion, but nothing serious because I’m careful. And keep the vinegar nearby in case you do get some on you.

      • JC says

        exactly! I tell people, no lye…no soap! period! now, if you want you could take the wood ash and make it yourself to be truly “natural” as they used to do before Red Devil came along. Lots more work intensive, but you will have a batch of real soap made with true labor of love!

  30. Carol Samsel says

    I use a crock pot for all of my soap making ♥♥♥♥ I will be trying the added water at the end to see how that works so I can do some of the fancy coloring methods. Thanks for sharing.

  31. jen says

    Thanks so much. This will be my first attempt at soapmaking, could I add a bit of oatmeal instead of herbs? I’m not sure if that would cook it and turn it mushy or not. Thanks!

    • Debra Maslowski says

      Yes Jen, you can. I add my oatmeal after I get the water part right after cooking the soap. I only use old fashioned oats because every time I use quick oats the soap gets slimy and has a terrible smell.

  32. Margaret H says

    I’ve made many batches of soap in the crockpot. I don’t like the smell of the soap while it’s cooking but the finished product is nice. I never tried your trick with water’s. But I will be sure go try it in the future.

    • Carol Samsel says

      I’ve made soap using lard and they come out fine…not as creamy as vegetable oils but they do work. Animal fats are what were traditionally used in soap making.

        • Debra Maslowski says

          I started out using animal fats instead of all vegetable as I do now. I only switched because I had so many people object to animal products. Lard makes a nice soft lather and a white bar. The bacon smell goes away after it’s saponified. I’ve also used tallow, chicken fat and buffalo fat. Didn’t like chicken, it went rancid. Buffalo was great, little smell and a nice hard bar with great lather.

    • Jaime says

      yes yes yes beef tallow makes the best and have read that it mimics your own skin. makes a very silky feeling bar of soap.

  33. Erin says

    Help! My daughters both have terrible exec a and I have been toying with making my own soap so it will be gentler on their skin. But my oldest is allergic to coconut, what can I use in its place? Thanks!

    • Carol Samsel says

      I’ve made soap with this method for years using olive oil and caster oil and love it. You can google for recipes…just be sue to run all recipes through a lye calculator to make sure you are using the correct amount of lye .

    • Jaime says

      Just use all olive oil and it will work great but after the cook time add 2 to 3 oz of raw shea butter it is great for healing the skin and so is the olive oil. Hope that helps good luck making soap it does get eaiser and I love it and usually do all hot process but have not added water at the end to smooth the soap out.

  34. Kristi ~ Hippie Chick Herbal Harmony says

    Great advice! I love the hot process, but when it comes time to add my “goodies”, the soap is always so hard to work with. I thought about adding water, but was afraid it would mess up my batch. This should help me swirl and blend better.
    I’m assuming by doubling the batch, I should also double the water after the cook.
    Think I’ll give this a try today!

    • Debra Maslowski says

      Hi Kristi! I’ve done both double the water and using just a bit more. It just depends on how much your soap has cooked down. And when I add powdered goat’s milk at the end, it gets really pasty, so I have to add more. The soap stays softer for a week or so, but then hardens up nicely. And I haven’t seen much shrinkage.

  35. Michele says

    I love hot process. My trick always involves playing with water amounts. Even in cold process, saponification is usually complete within 48 hours. My cold process bars are hard as a rock and ready to use within that time, because I don’t overdo water. All I eliminate is the curing process to release the water to make the bars hard enough. I use slightly more water with hot process because the bars are cooked to ‘done’ right away. I love soap making. It’s like my fudge making addiction, only less calories! thanks for the tips!

    • Sarah says

      Michelle, I am new at making soap. I am wondering if there is a cheaper way you have found to fragrance your soap. I like the essential oils but have found that you really do use a lot of that in one 2 lb. Batch. Any suggestions??

    • Debra Maslowski says

      Thanks, Michele! I’ve used most of my soap right away too, but some do take longer, so I usually tell people to wait. There is a lot of talk going on about water reduction and in the batches I’ve tried it with, it seems to be ready faster. Thanks for pointing that out.

  36. Monique says

    My very first batch of soap was hot process in the crock pot. We used it as toothpaste. It was easy!

  37. angelina says

    I would just like to add that this is a brilliant idea, just one thing though, instead of saying a 1/4 cup of lye, use a proper weighed amount using an online soap calculator like mountain sage. Lye needs to be properly calculated to make sure that after all your hard work you have a soap that is creamy and moisturizing and not harsh on you skin.
    Thank you for posting this
    angelina x

    • Debra Maslowski says

      That’s true, Angelina, for most recipes. However, I have come up with a recipe that uses cups, not ounces. I’ve already calculated the ounces and it’s the same every time if you follow these instructions. You can see the full recipe and instructions in the soap making article I did here a few weeks ago. For all other recipes, you would want to use a scale.

      • JC says

        as you can see by my blog name I am not one to be picky about measuring. I wing it! I have a fabulous recipe that gives in pounds for the fat & oz for the lye. I have always gotten soap not always pretty, but functional & rarely a fail! It needs little attention and I like it that way. I am eager to try this method however & will enjoy the smaller batch. My recipe gives me a year or more worth of body soap (when all the kids were still at home) with plenty for giving as gifts. Thanks for this new idea~

      • Ratna says

        Lye is not standard around the world. A cup of lye crystals from India weighs considerably less — i.e., there is less sodium hydroxide — than commercially packaged lye crystals in the US and Europe. I think the commenter who suggested that you include a weight is being wise.

  38. Dianne Finnegan says

    Thanks so much for this! I have been making cold process for just about 4 months and the last time I tried to make soap in a crock pot, well, lets just say I tossed it all in the trash. I look forward to making this soon. It will be nice to have a bar of soap that doesn’t have to sit around the house for weeks before I can use it!!

    • Debra Maslowski says

      Thanks Dianne! Like you, I was fed up with waiting and/or having soap that looked like it had been stretched out and shoved back together like taffy. It took me a few years, but I finally learned. Now that I have, I may never go back to cold process.