How to Make a No-Leak PVC Pipe Soap Mold (on the Cheap!)

Hello everyone! A here!

I like the shape of round pucks of soap. But the prices for round column molds are astronomical! So, I finally got around to making a PVC mold that costs $8.22 to make, including lining.

Materials You Need to Make Your Own Soap Mold

• 1 precut 3” diameter PVC pipe
• 1 Round Soap Mold from Brambleberry
• Cling wrap
• Permanent Marker
• Scissors

How to Make a No-Leak PVC Pipe Soap Mold

1. Clean the inside of your pipe.
2. Inspect each end of the pipe. Look for chips and scratches along the rims of each.
3. Label the end with the least amount of damage with something that catches your eye. I labeled mine with “PLUG THIS WAY” and doodled a bit.

PVC Pipe Mold Labelled (& Doodled!)

4. While the ink dries, take your Brambleberry mold and flip it over.
5. Use your permanent marker to draw a circle around one little silicone round. It should be about ¼” away from the round.

Using a Brambleberry Silicone Round Mold

6. Cut around the concentric circle. Lay your “plug” to the side.
7. Tear off a piece of cling wrap and wrap it loosely around the open end of the labeled side of your PVC pipe.
8. Press your cut out silicone round into the covered end of the cling wrap.

Use the Silicone Round to Plug the End of the PVC Pipe Mold

9. Flip your "plugged" pipe over. Pull out a piece of parchment paper (you can use freezer paper; I just prefer parchment when it comes to lining molds) that is longer than the length of your mold. Roll it into a tight tube, and plop it into your mold. The paper should expand to fit your mold. If it doesn't, just run your hand around the inside of the mold before you start filling your mold. (Tip from Kenna: If you grease the inside of the mold with Castor Oil or another thick oil, you can make the parchment paper stick to it just enough to keep it in place!)

Things to Note

• Remember that your plug is flexible silicone. That means that your plug can bend once you start to fill your mold. You can cut out a cardboard round that fits snugly into your plug. This will ensure that the bottom of your round soap log is completely flat instead of rounded.
• A mold like this holds about 95 ounces of soap.
• Pour soap into your mold at a pourable thick medium trace. This, along with the “plug” is going to be key in ensuring that your mold doesn’t leak. You can even get away with a thinner medium trace, but a thin trace isn't an option.
• The PVC pipe I used has a working temperature of 140⁰ Fahrenheit. When I gel soaps, I’ve seen temperatures get as high as 187⁰ F. I don’t think it would be a good idea to gel soaps in these.
• You’ll have to give it a push to get it to remove cleanly. Don’t get me wrong, it’s easy to remove, but once you remove your plug, rest your hand or even a DIY soap pusher and give it a bit of a push. Then use the excess parchment paper to start pulling the log out. It should remove quickly with little strain on your part. Try to make sure that your soap isn’t too soft or too hard.
• Make sure to swab the inside of your mold after each use!

How did it cost $8.22?!

I spent a little under $7 for the precut pipe. I bought the silicone mold from Brambleberry for $12.50, however, I only used one round of twelve. Divide 12.50 by 12, which is about a $1.04.

Though I don’t quite remember how much I paid for my cling wrap, I looked up the going rate online at Walmart. It’s $2.88 for 300 square feet of wrap, or $2.88 for 43,200 square inches. I used about 8 inches. Divide 8 by 43,200 and multiply the quotient by $2.88. This will yield the total cost of the cling wrap, which is about .00053 cents.

Parchment paper costs $3.48 for 45 sq feet (540 sq in). I use a 28” long piece of parchment paper to line the inside of the mold. Divide 28 by 540 and multiply that by 3.48. Lining this mold costs about 18 cents.

7 + 1.04 + .00053 + .18 = $8.22

Does this soap mold really work?!

I think so. I’ve made soaps that set up hard as rocks from the get and soaps that were soft upon unmolding. I’ve never had a problem with any of them. See? Look!

Whole Avocado Soap made in this PVC Pipe Soap Mold

A Palm-Olive soap made in this soap mold. This soap was extremely hard, despite the amount of olive oil!

Peanut butter soap made in this PVC Pipe Soap Mold. This one was quite soft!