Once you have a good recipe that you and your customers love, it is time to step it up.
So, how do you make soap in bulk? The best way to make soap in mass quantities is…
- Buy your ingredients in bulk (40% discount +/-).
- Use a bigger pot ($90) or HDPE plastic bucket ($35).
- Swap your stick blender for an electric drill ($30) with a long paint stirring drill bit ($8)
- Use a large mold with simple liner (make one for free or $15)
- Use a two-handed cheese knife ($29) or wire multi-bar soap cutter ($125)
- Expand your soap curing station ($20 to $150 depending on preference)
That’s all there is to it.
Optimal Bulk Soap Making Strategy: Start Small Then Expand
I set up my first bulk soap making operation for about $90, then expanded as the business grew. You do not need anything fancy. Simple works.
One of the best things about making soap is that you can double production with only about 35% more time and effort. If you know how, that is.
That’s exactly what you will learn here. There’s an easy to follow blueprint for successfully upscaling soap production with minimal cost or time investment.
The first thing to do – before spending a dollar on new equipment – is to understand “master batching”.
Master Batching
Master batching is the act of making a large batch of soap ingredients for incremental use. This could mean oils or lye solution.
When master batching oils you are preparing enough oil for multiple batches, usually with the intent of splitting it up to make variations of a similar soap. In some instances, you will use different milks, essential oils or exfoliates in each batch of identical oils to produce completely different soaps.
Other times you may add additional oils or butters to the master batch base, completely changing the final base. Shea butter is popular for this technique.
Finally, you might master batch just to have a large single batch of oils for a larger than usual loaf or block of soap.
No matter how you get there, it all boils down to this… Master batching is essentially multiplying the fat and oil amounts by the number of batches desired. The same is true of lye solution. You are simply making a giant batch of lye water so you can divide it as needed when you make smaller individual soap batches.
Example of Master Batching Oils:
| Oil Type | OZs for Single Batch | OZs for Triple Batch |
| Olive Oil | 16.00 | 48.00 |
| Coconut Oil | 14.00 | 42.00 |
| Almond Oil | 11.00 | 33.00 |
| Shea Butter | 6.00 | 18.00 |
| Castor Oil | 1.50 | 4.50 |
All we do is multiple the number of ounces in a single batch by the number of batches we want to make. Or, by the size of a large single batch that is x times as big a single batch.
If we choose to use all this oil for a single giant batch of soap, that’s fine. If we choose to beak it un into three different batches with the same base oils – also fine.
Insider Advantage
If you master batch often it is well worth it to have an accurate digital scale that measures up to the total weight of your batch – or of each oil individually. If you measure each individually, you will just need to use an interim container for weighing before adding it to the main batch.
I suggest a scale that can accurately weigh up to 10 lbs. (160 OZs). Going up to 25 lbs. is the next major leap. And finally, 50 lbs. will be the top-end capacity for accurate scales before you get into very expensive models.
You do NOT need to buy a new scale. It just helps save time and simplify the process of making large batches. With a more powerful scale you can weight 5x, 10x or even 20x as much at once. This is a huge time saver. It allows you to weigh out a 10x batch in just a little more time required than for a single batch.
Money Saver!
If you want to save some cash, consider using any scale in metric mode. While most off-the-shelf digital scales are accurate to 0.1 oz US measurement, this is because they are limited to one decimal place on the output screen. Switching from ounces to grams on that same scale can give you three times the accuracy. This is because one gram equals 0.035 ounces.
Now, let’s get back to those steps!
Step 1: Buy your soap ingredients in bulk (40% discount +/-).
We will look at some of the best soap specific suppliers here. However, don’t be afraid to think outside of the soap box. For oils, consider purchasing from restaurant suppliers. For tools, let’s look at hardware and home supply stores. For lye, consider chemist supply shops.
Remember; soap supply depots make it convenient to buy everything you need in one specialized location. But that specialization might not be as important to you as you start working in bulk.
Don’t get me wrong, some of these shops also provide priceless intangible benefits like great support, expert advice, free charts and calculator tools, and recipes. You should ALWAYS support these shops.
If, however, you are buying from a supplier that merely buys 50lb blocks of coconut oil and repackages it into ten containers of 5lbs each – why not just buy the 50lb block yourself and save the 40%? This, of course, is only if the quality is high.
Entertainment Overhead versus Expertise and Support
Have you ever gone to a movie theatre and bought a box of candy for $4 only to find the exact same box at Walmart for $0.97? This is because movie theatres keep ticket prices lower by charging a higher premium on snacks – and having a monopoly on them since you cannot bring your own.
Soap maker supply shops are nowhere near that level of markup. They might charge 30% or 40% or so over what you can pay a distributor directly – but that is reasonable considering what they give back. They need to pay staff for researching great information they share with you, offer top-notch support, and pay people to build those free calculators we all love so much. That said, it is important to support those shops that give back to the soaping community.
With all of that said, here are some of top-pick supply locations. These include soap specialty suppliers who give back to the soaping community in many ways, restaurant suppliers for oils, and hardware specialty outlets.
Soaper Suppliers
| Supplier | Variety | Loc. | Phone; cc: 1- |
| Wholesale Supply Plus | 106 | OH | 800-359-0944 |
| Bulk Apothecary | 33 | OH | 888-728-7612 |
| Brambleberry | 12 | WA | 877-627-7883 |
| Chemistry Store | 25 | SC | 800-224-1430 |
| Candle Science | 15 | NC | TXT 919-891-6226 |
| Candles and Supplies | 13 | PA | 800-819-6118 |
| Rustic Escentuals | 12 | SC | 864-384-5331 |
| Arizona Soap Supply | 18 | AZ | 480-401-1595 |
| The Gourmet Rose | 17 | OK | Not Available |
| New Directions Aromatics | 16 | Ont. | 800-246-7817 |
Note: Variety indicates number of melt and pour soap bases available. Melt and pour tends to be the more difficult item to find with good selection. For that reason, it is featured for your convenience.
What You Might Buy: Fats, soaping oils, essential oils, fragrances, exfoliates, molds, packaging, lye, botanicals, melt and pour base and pretty much anything related to soap making.
Special Tips: You can get soap oils, essential oils and most other standard soap making ingredients at stores other than soap specific suppliers. The exception to the rule is melt and pour soap base. Finding a high quality readily available supply can take some work. For that reason, the links in the table above go to the melt and pour pages of each outlet.
Restaurant Supply Houses
| Company & Link | Products of Interest |
| Webstaurant Store | Consumables: Oils | Hard Goods: Immersion benders; scales |
| Restaurant Supply | Hard Goods: Immersion benders; precision scales; pots |
| The Restaurant Store | Consumables: Oils | Hard Goods: Storage and curing racks |
| Restaurant Depot | Hard Goods: Pots; curing racks; high quality ingredient bins |
| Hotel Restaurant Supply | Hard Goods: Precision high-capacity scales; thermometers |
What You Might Buy: Consumables such as Lard, oils (coconut, olive, etc.). Hard Goods including large pots, commercial double boilers, cooling racks (for curing), commercial grade appliances (electric soup warmers, large slow cookers, industrial paddle mixers and stick blenders, etc.), thermometers, precision high-capacity scales and more.
Special Tips: Search for ingredients rather than just products if you don’t find what you want right away. For example, 100% palm oil is often labeled as “shortening” or something more specific like “donut frying oil”. Coconut oil is often listed as “popcorn oil”.
Also, be sure to read the descriptions for any certifications such as organic or sustainable. If you purchase something with a special designation, be sure to get proof. Then keep it on file with your batch notes.
Hardware Outlets
What You Might Buy: Large capacity (accurate) digital scale, power drill and paint stirring bit to replace your stick blender, materials to make large high-quality inexpensive molds, trash bags for mold liners, large mixing buckets, storage bins for keeping ingredients fresh, shelves for stock, racks for curing stations, and possibly lye (depending on the type you use).
Special Tips: When buying outside of a soap supplier always be thinking in terms of repurposing. For example: Plastic stackable shelves with slats in them might make great long-term soap curing stations. If you have some closet or wall space available, low-cost rubber-coated wire closet racks make fantastic curing racks.
Also keep in mind that lye is the #1 drain cleaning material used in the United States. I use food grade lye but many soapers make wonderful soap with 100% Sodium Hydroxide Lye labeled as “drain cleaner” in hardware stores. Just be sure it is 100% Sodium Hydroxide Lye. Also read the reviews. You will probably see more from soap makers than from people using it for drain cleaning.
Step 2: Use a bigger pot ($90) or HDPE plastic bucket ($35).
Upgrade to a larger pot to make bigger soap batches. The two greatest determining points of your pot selection are:
Intended use (oils only or saponification)
If you are only using the pot to combine and heat oils, you don’t need to be overly concerned about having a lot of extra free space for soap expansion.
If you use the pot for stovetop hot process soap making, you need significant room for the soap to expand during the “cooking” process.
When lye solution is added and the hot oils and hot lye water combine – they volcano up. This is not a problem with cold process, where the oils and lye are cooler when combined.
Size of the intended batches
Stock pots from the above suppliers, or Amazon, Walmart, etc. will typically be measured in gallons or quarts (US) or liters. This is important.
While a gallon of water weighs about 8.3 lbs. (at room temperature; at sea level) oils are lighter. Under the same environmental conditions of the water example, one gallon of olive oil will weigh 7.3 Lbs. while one gallon on 76-degree coconut oil weighs 7 lbs.
Heads Up!
I mention this weight difference because in soap making, we always measure recipes by weight (not volume). Pots are purchased according to volume capacity. That said…
Adding 128 ounces (8 lbs.) of water to a one-gallon pot will fill it to the brim.
Adding 128 ounces (8 lbs.) of olive oil to a one-gallon pot will make it overflow.
Adding 128 ounces (8 lbs.) of liquid coconut oil to a one-gallon pot will make it overflow even more than the olive oil.
This is because you are trying to fill a pot made to hold a specific volume of water, with the same weight of oils. The oils have a higher volume per ounce or gram than the water, so it takes up more space at the same weight.
This is NOT a big deal. I simply bought a slightly larger pot to be safe. Instead of a 10-gallon pot, I bought a 42-quart pot (10.5 US gallons). It is a brewer’s pot with a spigot on the bottom for easily pouring out the exact quantity of oil needed per batch. It’s perfect for my needs.
Step 3: Swap your stick blender for an electric drill ($30) with a long paint stirring drill bit ($8)
If you already have an electric drill, be sure to buy the right “chuck” size painter’s bit. The chuck is the collar connection that accepts the bit into the drill. Most electric drills that consumers buy use a 3/8” diameter drill bit. Most heavy-duty industrial drills use a ½” diameter drill bit.
The Mixer Bit
There are paint stirring bits for both chuck sizes. My drill takes 3/8” diameter bits. I bought the Premier mixing bit below for les than $4 at Walmart. It does not have the best rating for mixing paint but works great for blending my soap batter.
There are many types and styles to choose from. Most will cost between $5 and $15. Just make sure yours is made of steel – NOT aluminum. Aluminum and lye do not play well together. Never use aluminum pots, utensils or anything that can come into contact with lye. Stainless steel is your best bet for mixing paddles and bits.
Insider Advantage:
If you are unsure of your chuck size, buy a 3/8” diameter bit. It will work with either drill size.
The Drill
You do not need anything expensive. A cheap power drill from Harbor Freight will do the trick. Or pick one up used, for $10, on Craigslist.
Cordless drills are convenient but can eat up a battery charge quickly when doing multiple consecutive batches of thick batter. That said, if you go cordless, consider buying a second battery to keep on the charger. Having your mixer run out of juice halfway through the job is not good.
Step 4: Use a large mold with simple liner (make one for free or $15)
When making large quantities of bar soap, there is no need to get fancy with a mold or liner. Just about any lined rectangular box shape will do. I started off by buying large professionally made molds and they are wonderful. They are also expensive and can take weeks to arrive.
Finding a Simple Box Mold
You can use deep trays, square edged baking pans, even trough-style flower box planters. Start looking around your house and soon everything you see will look like a box mold. Old wooden dresser drawer? BIG box mold!
The only requirements for the mold are…
- The edges should be square. The corners should also be 90 degrees and straight in all directions.
- Most baking and pans have curved edges instead of right angles.
- It’s best if the size is easily broken into even sections of the desired individual loaf sizes.
- If your bars are to be 3” wide, the mold width should be evenly divisible by 3” (or close). You can always add ¼” or ½” thick planks of wood as shims to make it the right size.
- The material should retain its shape with heavy soap batter added.
- Cardboard will likely bow. You can fix this by adding some straight wooden planks around the sides to support the shape.
- If used for cold process soap making, it must be able to withstand the prolonged temperatures that occur during the lengthy saponification process.
- If it comes with a cover – even better.
Insider Advantage
When I started getting into batch sizes of 25 lbs. or more, it was tough on my back to lift and flip molds. I found that a slide-out bottom, or removable sides, helped a lot.
Making a Simple Liner
Liners are super easy. Parchment paper is great but can get a little expensive after a while. I have also had “uh-oh” moments where I ran out halfway through lining the mold.
Something that works surprisingly well as a mold liner are cheap plastic trash bags. It takes a bit of practice to crease the seams well enough to avoid all wrinkles. But it’s a skill well worth learning.
I like to use an over-large bag and cut the bottom out. The I slide my box mold into it like a sleeve. I had an old wooden spoon handle that I repurposed for creasing. A few seconds in the pencil sharpener gave it a good shape – stopping short before a point formed. Then I used an emery board to file a 90-degree edge that fits perfectly into the side and bottom mold connections to crease the bags.
You can use a fingernail just as easily. A friend of mine swears by using the square end of a chopstick that she gently filed with a sanding block.
Each bag costs a few pennies and can be recycled. The real benefit to me is the time savings and convenience. After I got some practice, I could line a box mold in less than 20 seconds and clean up is even quicker!
Thinking Inside of the (Soap) Box
At one point I received an order much larger than expected and needed to step up production quickly. My 42-quart pot could master batch the oils. And I had several 7-gallon HDPE buckets that I use for combing the soap batter with lye solution. So, this was not a problem. However, my soap needed more molds.
There was no time to order more of the beautiful Baltic Birch box molds with custom silicone liners that I was accustomed to. There would barely be enough time to go to Lowes and get the wood to make my own. And honestly, my husband loves doing projects like this and I am more than happy to let him help.
I remembered seeing some cute wooden curio boxes at Michael’s craft store. The inside dimensions were a little over 8” wide by 11” long by 4.5” high. Perfect for a triple batch! They even came with nice pull off covers. The wood was thin, and light but more than sturdy enough for holding my soap and making perfect triple batch blocks.
My batches were made via stovetop hot process. I did not need to worry about the thin wood being exposed to prolonged excessive heat during saponification. I bought three of these boxes at just under nine dollars apiece.
I used parchment paper to line each box, careful to reinforce the corners to avoid soap batter touching bare wood. Each box mold produced 33 perfect bars. I was able to make 99 bars of hot process soap in just a few hours thanks to master batching my oils.
Important Notes:
- I used a hot process method that involves using the heat of the oils and lye water to complete the “hot process”. This means I was able to use the spigot on my brewer’s pot to measure the needed oils into buckets while still extremely hot.
- I did not master-batch the lye because heat from the lye solution is also part of the “cooking” process for this method.
- Opening a tap on the pot and making each triple batch in a 7-gallon HDPE plastic bucket allowed me to safely work at my own pace and not take any unnecessary risks. The height of the 7-gallon bucket is ideal because this hot process method mushrooms to more than double its size in the pot.
Step 5: Use a two-handed cheese knife ($29) or wire multi-bar soap cutter ($125)
Loaf Splitters
When making large blocks of soap in box molds, you will need a “loaf splitter”. This just means you need to cut the giant soap blocks into usable loaf sizes. Once they are regular loaves, you can use a blade or wire multi-slicer to cut perfect bars from any length mold.
You can also buy a wire loaf splitter or other blade-type models. For me, they take up more space than I want to dedicate. But before I was comfortable with my big two-handed blade, I would have given anything for a good soap log splitter. Fortunately, at the time I could not justify the expense, so it forced me to get good with a big knife.
I use a two-handed cheese knife to cut my blocks into loaves. The trick is to stand over it and cut straight down to get a good straight cut. Wire cutters do not work on melt and pour soap, so I use this blade, or a small slicer to cut the MP bars as well.
Here is my two-handed blade. The brand is “Mundial”. You can buy them on Amazon in different lengths. Mine has an 18” blade length. It cost $31 when I bought it in 2018. A lot of specialty cutlery stores sell these for double that price.
Here is a simple soap cutting box and blade. You can also get these on Amazon or any soap supply shop. This one comes with a straight cutter and wavy cutter. It will typically cost from $16 to $24 depending on the material it is made of. The bamboo model below was $21 on Amazon when I purchased it in 2018.
Multi-bar Wire Soap Cutters
This is where I decided to splurge. Up until 2019 I still cut all my bars by hand. It’s rewarding but takes a lot of time. My blades are razor sharp, so I never rush.
I paid $140 for this 12” bar cutter and it has paid for itself many times over.
You place the entire loaf on the cutting surface, pull down the top. In seconds, you have 12 perfect 1” thick bars of soap ready for packaging.
Be Aware!
Wire cutters like this work on cold process and hot process soap – but NOT on melt and pour. You will break the wires and potentially injure yourself.
Step 6: Expand your soap curing station ($20 to $150 depending on preference)
Expanding your curing and storage areas can be as simple as adding some slatted shelves. But here are some ways to do it a bit better.
Get shelves that will allow for maximum airflow. Plastic shelves with slats are good, but rubber coated wire racks allow more airflow from the bottom. If you only have solid shelves, buy some cookie cooling racks at the Dollar Store. They work just fine.
Try to find a cool dry place with good air circulation to set up your shelves. If you are placing multiple sets of shelves, try to keep them at least six inches apart for circulation.
Set up your shelves so you have at least six inches of clearance between the tops of the bars and the bottom of the shelf above. This allows for better circulation for both shelves.
If you have a dehumidifier, it is worth it to set it up as near the center of your rack arrangement as possible. If not, you can buy silica moisture containers for $1 at Walmart. People put these in laundry closets in humid areas. They work very well. Just be sure to replace them when they get full of water.
If you have a ceiling fan in the area, that can work well. If not, consider adding a couple small oscillating fans to two opposite corners of the area and running them for a few hours per day.
Insider Advantage
I had limited space to work with. But I also had a cheap old wardrobe cabinet that was ready for the dump. I cut a small hole in the top of the right side and another in the bottom of the left side. Using a hot glue gun, I stuck on two small reclaimed computer fans my husband had in his “treasure” pile. He handled the wiring for me. The motors were DC and he put on some little “AC adapters” so I could just plug them into a power strip.
The top fan draws air in. The bottom fan sends it out. It had no shelves as it was meant for hanging clothes. I used some cheap rubber coated wire racks from Home Depot as shelves. Then I stuck two silica water catchers in the bottom. It works great!
I even painted the outside a shabby-chic and had some fun with it.
In closing
Hopefully this information helps get your expansion into making bulk soap. If you are interested in making melt and pour soap in bulk, there is another post on this suite you might like… Making Melt and Pour Soap in Bulk