I’ve been on a bit of a slab mold journey over the last three years and learned a few things along the way that I detailed below in case anyone else is thinking about buying a slab mold. Early on I was always looking for small slab molds because I typically don’t make soap with more than 1000 g of oils. Over time, I developed a preference for bars that are 2,5”x3.5” in size and I want minimal cutting waste. Many slab molds won’t tick all three of these boxes.
The first slab mold to join my collection was a cardboard candy box, which is a great way to go if you’re new to soap making. Then I added my trusty 6”x6” silicone mold. These are easy to find and made of very durable silicone. I’ve gotten a lot of mileage out of that little mold, love that it doesn’t have to be lined and still use it to make four 3” square or six 2”x3” bars. Next up was the bottom tray for a slatted wooden bread cutting board that I found at a thrift store for about 99 cents. It works well, but is shallow and I have to line it with freezer paper.
Next I bought the blue silicone loaf mold in the photo below. It was relatively inexpensive and works well for slab-like single layer wall pours along the long wall. The interior dimensions are close to 5”x 10+”, which yields eight bars that are close to 2.5”x3.5”. On the downside, the mold is a bit floppy, which makes it tricky to tilt and to move. There’s also not a lot of working room for a design like a cosmic swirl and it’s not a good shape for a spin swirl. The soft sides don’t distort for a single layer soap, but they bow out when the loaf is filled to the top (2.5” depth). I’ve used a lego crate to cradle this mold, but a wood box would be even better and making one is still on my to-do list. The divided wood mold was a Christmas present last year. Honestly, I only used it once and without the dividers, partly because I do not like lining molds. At 1.5” depth, it’s a bit shallow to tilt, which is something I like to do to get the soap to move across the mold when I’m doing a wall pour in a slab mold. I personally wouldn‘t try to use it for a spin switl because I can be messy. Using the dividers would yield nine bars that are a hair over 2”x3”. They are a bit wonky looking, but might stay straight in a full mold. I made eight 2.5”x3.5” bars and some smaller pieces by following the black marks I put on the sides.
Next(?) I bought a pricey acrylic mold (5”x7” by 3+” deep) with a silicone liner. It works really well for making four or eight 2.5”x3.5” bars and is easy to tilt. I love that I can see through the side of the mold to get an idea how the colors and layering are playing out below the surface. The liner is flexible but sturdy and it’s easy to get the soap out even when I make eight bars. It’s one of my favorite molds overall. On the downside, the combo of smallish interior dimensions and reasonable height of the mold makes it very challenging to pour close to the surface of the soap when I’m making four bars. I bought the relatively inexpensive 10+” square silicone mold to make column pour soaps for a recent SMF Challenge. It’s a bit flimsy due to size, but a cutting board takes care of that problem. I wouldn’t try to use it for a spin swirl since it’s only 1.5” deep, but I expect it will be really easy to work a design close to the soap surface in this mold and it’s a great size for the pipe divider swirl. It makes twelve bars that are close to 2.5”x3.5”. It’s not a mold I will use regularly due to the size, but it’s good to have on hand.
Last but not least, here’s my newest mold. With the dividers it yields nine 2.5”x3.5” bars that can be up to 2.5” tall. I plan to fill it to 1.5” depth to leave some room for planing the soap tops. With interior dimensions just under 8”x11”, it should give me the room I need for pouring close to the soap and it will also be easy to tilt. It’s also plenty high enough to do a spin swirl without sloshing soap out of the mold. A consideration with dividers is the resultant smear pattern on the side of each soap, but I also have the option of not using the dividers. I‘m hoping that I won’t have an issue separating the soap from the dividers based on the amount of hard oils and butters in my recipes. I may give this mold a trial run tomorrow. Please keep your fingers crossed that I don’t lose my mind and add an accelerating FO Into the mix!
The first slab mold to join my collection was a cardboard candy box, which is a great way to go if you’re new to soap making. Then I added my trusty 6”x6” silicone mold. These are easy to find and made of very durable silicone. I’ve gotten a lot of mileage out of that little mold, love that it doesn’t have to be lined and still use it to make four 3” square or six 2”x3” bars. Next up was the bottom tray for a slatted wooden bread cutting board that I found at a thrift store for about 99 cents. It works well, but is shallow and I have to line it with freezer paper.
Next I bought the blue silicone loaf mold in the photo below. It was relatively inexpensive and works well for slab-like single layer wall pours along the long wall. The interior dimensions are close to 5”x 10+”, which yields eight bars that are close to 2.5”x3.5”. On the downside, the mold is a bit floppy, which makes it tricky to tilt and to move. There’s also not a lot of working room for a design like a cosmic swirl and it’s not a good shape for a spin swirl. The soft sides don’t distort for a single layer soap, but they bow out when the loaf is filled to the top (2.5” depth). I’ve used a lego crate to cradle this mold, but a wood box would be even better and making one is still on my to-do list. The divided wood mold was a Christmas present last year. Honestly, I only used it once and without the dividers, partly because I do not like lining molds. At 1.5” depth, it’s a bit shallow to tilt, which is something I like to do to get the soap to move across the mold when I’m doing a wall pour in a slab mold. I personally wouldn‘t try to use it for a spin switl because I can be messy. Using the dividers would yield nine bars that are a hair over 2”x3”. They are a bit wonky looking, but might stay straight in a full mold. I made eight 2.5”x3.5” bars and some smaller pieces by following the black marks I put on the sides.
Next(?) I bought a pricey acrylic mold (5”x7” by 3+” deep) with a silicone liner. It works really well for making four or eight 2.5”x3.5” bars and is easy to tilt. I love that I can see through the side of the mold to get an idea how the colors and layering are playing out below the surface. The liner is flexible but sturdy and it’s easy to get the soap out even when I make eight bars. It’s one of my favorite molds overall. On the downside, the combo of smallish interior dimensions and reasonable height of the mold makes it very challenging to pour close to the surface of the soap when I’m making four bars. I bought the relatively inexpensive 10+” square silicone mold to make column pour soaps for a recent SMF Challenge. It’s a bit flimsy due to size, but a cutting board takes care of that problem. I wouldn’t try to use it for a spin swirl since it’s only 1.5” deep, but I expect it will be really easy to work a design close to the soap surface in this mold and it’s a great size for the pipe divider swirl. It makes twelve bars that are close to 2.5”x3.5”. It’s not a mold I will use regularly due to the size, but it’s good to have on hand.
Last but not least, here’s my newest mold. With the dividers it yields nine 2.5”x3.5” bars that can be up to 2.5” tall. I plan to fill it to 1.5” depth to leave some room for planing the soap tops. With interior dimensions just under 8”x11”, it should give me the room I need for pouring close to the soap and it will also be easy to tilt. It’s also plenty high enough to do a spin swirl without sloshing soap out of the mold. A consideration with dividers is the resultant smear pattern on the side of each soap, but I also have the option of not using the dividers. I‘m hoping that I won’t have an issue separating the soap from the dividers based on the amount of hard oils and butters in my recipes. I may give this mold a trial run tomorrow. Please keep your fingers crossed that I don’t lose my mind and add an accelerating FO Into the mix!
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