First, there is some stuff that you should just know. For starters, Lye is dangerous. It can burn skin (especially if you have sensitive skin). It can also destroy aluminum, so don’t use aluminum. Glass is preferred for all measuring cups and dishes. Plastic is OK, but glass is better. When it comes to silverware, make sure it is stainless steal. You can tell if your silverware is stainless steal or aluminum by putting a kitchen magnet against it. A magnet will stick to a stainless steal spoon, but it will not stick to an aluminum spoon. Don’t use aluminum!
I tend to do big batches of soap because once you start, it’s a long process and I rather do a bunch than a little. BUT, if you mess up, that means that you would lose a bunch rather than just a little. Also recognize that I am far from a professional soap maker. I dink around and make OK soap. If you read around online you’re going to find a lot more specific directions, but I’m just not willing to put that much effort into it, so I end up with mediocre soap that meets my needs (it also allows me some room to be sloppy and not ruin anything).
I’m going to give a list of what you need, and you likely have most, if not everything, on the list. But I will warn you that everything that you use in soap making will develop a layer of slimy soap type stuff on it. You can wash it off eventually, but mostly you scrub and scrub and scrub it and just keeps making bubbles (It’s like trying to wash a bar of soap). I have a designated set of soap stuff that I picked up at goodwill, but it isn’t necessary.
What you’ll need:
- A good scale (something that measures to the nearest gram or 1/10th lb)
- A variety of fats
- Lye – you’ll find this at an ACE hardware (big box stores don’t carry it) It will be with the drain cleaners. Red Devil is one common brand, but anything that is 100% Sodium Hydroxide will work.
- Glass measuring cup
- Stainless steal spoons
- Big plastic bucket
- Molds (baseball card boxes lined with wax paper work great)
- Emersion blender or drill with paint mixing attachment
The first step is to choose the fats that you are going to use. If you go to thesage.com and go to the lye calculator, you’ll find a huge list of possible fats that you can use in your soap. If you click on the fat, it will take you to the sales page that will tell you some of the properties provided by adding that fat to your soap. There are some cool possibilities, I’ll give some ideas from what I’ve tried.
Lard or Tallow– It works great for making a good hard bar of soap. I’ve always gotten mine for free from friends or by begging for trimmings at a local butcher (they usually say no, but if you get an inexperienced employee they’ll sometimes bring you something… and then you have to render it). This has generally been the biggest part of my soap recipes
Olive Oil – If this is the primary ingredient, it is a ‘castile soap’. It also makes a good hard bar of soap and I believe is good for sensitive skins.
Coconut oil – This is what makes a soap lather well. I’d call it essential (but only needs to be about 5% of the fats). I made a soap without it once (almost entirely from lard) and it didn’t lather and was stringy and gross… but it felt cleansing.
Castor Oil – It’s found in the pharmacy. It makes a soap have some conditioning properties if you want to make a shampoo bar of soap. I don’t have a lot of hair and I am not much of a connoisseur of shampoo… it worked fine.
Corn oil – It’s really cheap and makes a really cheap feeling bar of soap… Don’t bother.
Canola oil – It works fine and is a good, inexpensive additive that helps make for bigger, cheaper batches, but it also makes the entire process take longer… maybe LOTS longer!
Beeswax – I like to think that it makes a nice smell and a nice hard bar of soap, but I don’t know that I’ve ever really noticed that. I happen to have it around, so I use it.
Those are the fats I’ve used… Here is a website with a good list of properties: http://summerbeemeadow.com/content/properties-soapmaking-oils
So you will decide what fats you’ll use (and I’m not giving you a recipe because I tend to just weigh the fats as I add them and use what I have. I’ve never made the same recipe twice) Weigh the fats very precisely, remembering to tare the weight of the measuring cup and put them in a big bowl (I generally use an aluminum bowl because this will never be in contact with lye and it will go in the oven to melt the fats).
So I’ll weigh the fats as I put them in my big bowl and I’ll end up with a list with exact weights, such as: 500g lard, 50 g coconut oil, 345 g olive oil…. Etc.
I then put the fats in the oven at a relatively low temperature to make sure they’re all melted and mixed. While they’re melting I get the lye ready.
These measurements need to be precise and then you need to go type in those numbers to thesage.com lye calculator. Go to the bottom of the page and click ‘calculate lye’. It will do the math for you and then give you a range of how much water and lye you need to use. I tend to use the bottom side of the range for water and around the 5-6 range for lye (when you see what thesage.com gives you it will make sense). Nobody in my family has sensitive skin, and I like a good hard bar of soap. If you have some sensitive skin, you might lean closer to the 6-8 range, but I’ve made some soft bars of soap and I don’t like them. You can do it however you like it. That’s the beauty of doing it yourself.
Put the right amount of water in a glass measuring cup and then add the exact amount of lye to that water. Don’t breathe it, it produces some nasty fumes… and you should probably do this outside or under a good fan. You’ll need to mix it with a stainless steal spoon because it tends to clump at the bottom… Remember not to breathe it. A chemical reaction is going to happen with your water and lye and it will get hot!.
This is a point where a lot of people get crazy specific with temperatures and perfect timing to get perfect soap. I tend to rely on luck and end up with good enough. Instead of a thermometer, I try to time it so that my lye solution is still hot (about 5-10 minutes after mixing it with the water) and my fats are just melted (and therefore pretty hot). I then put the fats and then the lye solution into a big plastic 5-gallon bucket. I use a bucket that is substantially larger than the amount of soap I am making because it can get messy with splattering soap.
Oh, and there was a time when I didn’t get my temperatures right (I let either the fat or lye cool down way too much) and when I mixed them it sort of blew up. Not like an explosion, but a mass amount of bubbles (glycerin is what is produced, FYI) that just sort of flowed everywhere… It was a disaster.
Now you need to mix it. Optimally you would use a good quality emersion blender. On two occasions I have used an emersion blender and both times my soap project killed the emersion blender (one was made of aluminum parts and literally fell apart into my soap… it was pretty cool). The emersion blender can make it go LOTS FASTER, but my wife doesn’t allow me to use it anymore. I now use a drill with a paint mixer attachment (that is either steel or coated with plastic).
Now starts a process of mixing for 15 minutes and then letting it sit for 15 minutes (or so, it doesn’t have to be perfect). This could take between a few minutes and a few hours. Using fats like lard and tallow make it go faster. Fats like canola make it take longer. Using an emersion blender makes it go much faster. The drill technique is OK, but not nearly as fast as the blender. Doing it by hand might take you days.
So keep mixing until you reach ‘trace’. Trace is sort of what it sounds like. If you run a spoon (or the blender while it’s turned off) through the solution it will leave a trace or a mark in the top and take several seconds (the more the better, to a certain point) before it all looks level on the top again. This is obviously a thickening process, so there are several stages of thickness. Sometimes it seems like it takes forever and sometimes it suddenly goes really fast. You just have to be prepared. If you want to add essential oils or other scents, you would do this at ‘trace’. If you do it too early the chemical reaction of the soap will destroy the essential oil and it won’t smell like anything. If you do it too late, it won’t mix in and you’ll have pockets of essential oil in your soap. … So I don’t bother, it’s too complicated for me. Although I have added honey and chopped oatmeal once and that turned out well as exfoliants.
As soon as your solution has reached trace and you’ve added what you want to, you should put your soap into molds. I have used 4” PVC pipes that make little cylinders of soap (but it’s a pain in the butt to get the soap out of the pipes). I think my favorite method is to use baseball card boxes. You have to line the boxes with wax paper or it will soak through the box and leave a bigger mess than you can imagine. They also make nice wooden boxes or cute shapes that you can pay for. I’m too cheap.
So you pour the soap mixture into the molds. It’s thick, so a spatula might be helpful. It’s also still going to be very harsh, so rubber gloves might be in order. Make sure you have enough space to hold the content of your bucket.
Let the soap sit in the molds for a day or two and it will get fairly hard. When it is hard enough to handle, remove it from the molds and cut it into ‘bars’. Try to set it out in a way that all sides of each bar is exposed to air. The soap is still pretty harsh, and it needs to cure for at least 3 weeks. The longer you let the soap cure in a spot with low humidity, the harder the soap will become. Soap that has sat around for a couple of years is the best… But it is ready to use in 3 weeks. This is another reason I make big batches, it makes enough so that much of it sits for a long time before being used.
Oh, and then you will have to clean up. You’ll have all sorts of stuff covered in soap. Scrub as you may, it will just make more bubbles and maintain its slime. That is why I just put it away and use it the next time I make soap.
And then, if all went well, you’ll have soap.