No matter how many times I’ve put this project off, I always find myself saying, “I need a silicone mold!”. The thought of having a stockpile of silicone molds to choose from whenever I need to replicate a piece of work, sounds amazing. Why sit and try to reproduce a complex design for hours, only to end up scraping it because it’s nothing as good as your first piece? Art really is one of a kind, isn’t it? Or is it?
Time and time again, I’ve researched silicone mold making kits, which often range from $25 to $40, but only produce a single mold. I can never bring myself to make the purchase because it seems you get so little product for the price you pay. As a maker, the lightbulb in my head went off, and I began to think of ways I could create DIY silicone molds, and hopefully, for a fraction of the cost. I could potentially use this for projects including candle making, clay sculpting, and resin pouring. This would help me to save a ton of time!
After shopping in my own basement, I found two unopened tubes of silicone caulk, so I started digging. I came across several tutorials online that suggest a DIY silicone mold can be made by using 100% silicone caulk and various household materials. However, as I went through more and more tutorials, they all seemed to have conflicting views about the type of silicone to use and how much product was needed. I also couldn’t find a single tutorial that mentioned using white silicone caulk as opposed to clear and whether or not that made a difference.
I decided to experiment with this budget-friendly DIY project and determine for myself if you can really save with a do-it-yourself option or if purchasing a two-part silicone mold kit is truly worth the investment.
Depending on the household items you have available, you can try one of two methods for this project. Method one involves mixing silicone caulk with dish soap and water and method two uses cornstarch.
The Dish Soap Method
What you’ll need:
- (1) 10oz. tube of 100% silicone (any purpose and color will do)
- Caulking gun
- 1/3 cup of Dish Soap
- 2 cups of cold water
- Disposable container
- Wax paper
- Pair of nitrile gloves (optional)
- Object you wish to mold
- Face mask (optional)
Caution: Make sure you’re in a well-ventilated room. The silicone caulk has an extremely strong vinegar-like odor that may cause headaches. Cracking a window and using a mask are encouraged.
I highly recommend trying this tutorial first with an object that doesn’t hold much value to you. Although my objects were able to release from my molds with ease, there is a chance that the silicone to soapy water ratio isn’t quite right or that your mold didn’t quite set before trying to remove it.
Step 1
We’ll be following a recipe for creating a mold close to 2×2 inches or the size of a golf ball. The process for these DIY molds is really quite simple; the hardest part is having patience.
You’ll want to begin by filling your container with about 2 cups of very cold water, which helps to harden the silicone.
Step 2
Add about 1/3 cup of dish soap into your container. You’re looking for roughly 80% water to 20% dish soap.
Step 3
Set up your caulking gun with your silicone tube and give about 4-5 squeezes into your soapy water mixture. You can measure this step by eye, but it should be close to that of a golf ball.
This next part will be VERY sticky! Whether you’re using nitrile gloves or your bare hands, it’s best to prep your hands with the soapy water mixture so that the silicone caulk does not stick.
Once your caulk has been added, you’ll want to begin molding and folding the mixture within itself inside the container.
Work it within your hands like you’re kneading dough and incorporating the soapy solution into the silicone caulk. This is where patience is important. It may feel like ages, but eventually, it will lose its tackiness, and you’ll be able to hold it in your hands without the need for additional soapy water.
Step 4
After about 10-15 minutes, your mold should be easy to handle. You can keep the mold within your container while you lay out a sheet of wax paper. Note that once you lay the mold onto the wax paper, it will stick. Roll your mold into a ball or rectangular shape, whichever will better cover the object you’re molding, and place it on the wax paper.
Step 5
Now you’re ready to place your object into your mold! Your mold is likely to spread out once you push down, so adding a barrier to the edges can be helpful.
Once your object is in place, let your mold sit for 24-48 hours to cure.
The Cornstarch Method
What you’ll need:
- (1) 10oz. tube of 100% silicone (any purpose and color will do)
- Caulking gun
- 4-5 heaping tablespoons of cornstarch
- A Ziploc bag or disposable container
- Spoon
- Wax paper
- Pair of nitrile gloves (optional)
- Object you wish to mold
- Face mask (optional)
Following a similar process to the dish soap method, we’ll be making a mold about the size of a golf ball. Toss on your gloves and mask, if you have them.
Step 1
Add 4-5 heaping tablespoons of cornstarch to your sealable sandwich bag or disposable container. Although this technique isn’t as sticky as the dish soap option, you may find yourself in a bit of a cornstarch mess; this is where the Ziplock bag comes in handy.
Step 2
Use your caulking gun to dispense silicone caulk into your bag or container. About 4-5 squeezes should do.
After adding caulk, zip up your bag and begin squishing and folding the mixture until all of the cornstarch is incorporated. If you’re using a disposable container instead, you’ll want to use your hands (similar to method 1) until the mixture feels similar to play-dough.
Within 5 minutes, your mold should be easy to handle.
Step 4
Lay out a sheet of wax paper, roll your mold into a ball or rectangular shape, whichever best suits your mold, and place it on the wax paper.
Step 5
Depress your object into your mold and make sure the edges of the mold are flush with your item. If your mold has stretched outward, you can create a barrier to contain it or use your hands to build it up.
After setting your piece into your silicone mold, let it sit for at least 24 hours to fully cure.
How Will I Know My Silicone Mold is Ready?
The cornstarch method did seem to cure quicker than the soap method, but you should let your molds sit for at least 24 to 48 hours.
Soap Method
You can check that they are cured by depressing the sides of the mold. When using the soap method, it remains gummy-like and should spring back after removing your finger. You can also try to make an imprint in the side of the mold with your fingernail or a sharp edge. If it doesn’t take, then your mold is ready; if it holds, then give it more time.
Cornstarch Method
Using cornstarch creates a completely different textured mold. It becomes very firm and will also not leave an imprint.
Which Method is Better?
It’s hard to determine a true “winner” between the two since both, to my surprise, preserved detail quite well.
I did find that the cornstarch method was far less messy, plus it was quicker to make. However, the dish soap method did leave a shinier finish on the hardened resin. I can see a few projects where both would be useful.
Worth the Hassle?
As a quick and easy way of creating a custom mold, I’d say they do the job. It’s a cost-efficient way to achieve textures and can be an option for a simple resin pour.
I’ll be testing out a two-part silicone mold making kit in the near future for an upcoming product on my Etsy shop. I plan on sharing that process and the differences in quality in a later blog post.
Share Your Results
Have you given this tutorial a try? I’d love to see your results! Share pictures of your finished molds with me on social @linamakesart or email lina@linamakes.com.
