If you’ve wondered how to make a silicone mold, the good news is that it’s easier than you might think.
All you need to use is two-part silicone mold putty.
Here’s why it’s THE BOMB to make a silicone mold:
✅ You don’t need any fancy equipment.
✅ Molds are food safe.
✅ You can have a ready-to-use mold in 30 minutes
Step 1: Prepare your work surface.
Make sure your working surface is clean. Cover it with a wax paper sheet, then tape it so it won’t move.
Step 2: Get everything ready.
Once you start mixing the mold putty, you must be ready to use it. That means having the items you’re molding ready as well. Be sure they’re clean and free of any grease or dirt. If you don’t, that will transfer to your silicone mold.
⭐️ BONUS: If you aren’t sure what to use for your model, check out this mold-making article.
Step 3: Measure and mix the putty.
This putty mixes one part A with one-part B. You can ‘eyeball’ equal amounts of putty to mix it. You can also measure the parts by weight if you have a scale.
💡 Pro tip: It’s pretty forgiving when it comes to mixing. I’ve never used a scale to mix it, and my silicone always cures perfectly.
Once you measure the two parts, smash them together until they are evenly mixed. This takes about 1 minute. The putty is mixed when the color is even throughout. You shouldn’t see any streaks.
You only need to mix enough molding putty to cover and surround the item you’re molding.
💡 Pro tip: I usually only mold one thing at a time instead of mixing a bigger batch for a few items.
Step 4: Press the putty around your model.
Once you’ve mixed your putty, roll it into a ball bigger than your model. Flatten the ball slightly, then place your model into the flattened area. Roll the putty over the object until it’s covered, pushing in somewhat on the sides and corners.
Don’t push too hard. You want to leave putty at least half to three-quarters inches thick around all sides. If you don’t, it can rip when you demold your item.
💡 Pro tip: Use a Popsicle stick to push on the sides and flatten the bottom of the mold. This lets your silicone mold sit level when you pour your epoxy resin into it.
Work quickly. You only have about two minutes to mold the putty around your model once mixed. After that, the silicone won’t be workable anymore.
Set your mold putty aside to cure for 30 minutes.
Step 5: Demold.
Remove your model from the mold by pushing the sides to loosen the template from the mold walls. After a few pushes, your model should pop out easily.
Your mold is now ready for polymer clay and epoxy projects. The molds are also great for soap or candle making. You can also make molds for food projects like chocolates, candies, and ice cubes.
💡 Pro tip: You want to use a casting resin in your mold to get the best bubble-free results.
Want more help on how to make a silicone mold?
This video, courtesy of Meredith of Cosmic Designs, shows you how to make a simple silicone mold that’s ready to use in 30 minutes.
You can also see how to use two-part silicone putty to make a lego mold.
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I learned a new technique from you. Your mold is really good. I like how you drop your putty ontop of your item. I was going the wrong way.
I was going the other way too! I must try it your way, looks like you will get a better impression and mold… Thanks so much for sharing
I really like how you did this but is there a way to make a mold of something you dont physically have? I want to make Kida’s necklace from Disney’s Atlantis only I dont have the physical shape of the crystal to mold with. How should I go about it?
Cam,
You can’t make a mold of something without a physical model. What I would recommend in this case is to find a wax carver (we can hook you up with one) to carve a model for you. You can then make a silicone mold from this wax model.
I like it
Cam – It’s totally possible to make a mold without having a physical object. All you need is a 3D modeling program like Maya or Zbrush for your computer and enough skill in using it to create a 3D render of the object. Considering the simplicity of the crystal, it should only take about 30 minutes. Once the 3D render is complete, invert it. Then send the file to a place like Shapeways that does 3D printing. You can have a perfectly detailed mold delivered to you and ready for use within a couple days.
I have a plaster (I think its plaster) of a sailing ship. It’s approx 22 inches tall, 18 inches wide and the highest point is approx 1 inch. It has some intricate details and the back of it is flat.
I would like to make a silicone mold or other material that is suitable for epoxy resin. I want to make an export resin of this piece in other words
I’m a total newbie with molds. Any pointers?
I would like to make a mold and molding
Using your products. I live in South Africa and would appreciate any help in getting the products here.
Dave King.
Hi Dave, we do ship products to South Africa when allowed. You will be given shipping options at checkout.
Thanks for the article Katherine. I’m wondering if I can use an epoxy item as the physical model for my silicone mold?
Background story: I created a free-form mold using silicone caulk, my resin item from that was a bit rough on the sides, so I dremmeled and sanded and polished and now it’s perfect. So I’d like to use that resin item to create a better mold for my future projects.
Hi Laura, yes, you can do that.
I want to make a mold for a 52 inch round table top. I can find premade molds up to 48 inches but wanted a bit larger. Is there a way to make one myself?
Yes! You can absolutely make a custom mold for a 52-inch round tabletop. Here’s a guide to help you create a durable, reusable mold for large resin pours:
Materials You’ll Need:
Melamine board or MDF (for the base and sides)
Circular saw or jigsaw
Measuring tape and compass (or string and pencil for drawing the circle)
Silicone caulk (100% silicone)
Clamps or screws
Painter’s tape or release agent
Hot glue gun (optional for securing pieces temporarily)
Steps to Build the Mold:
1. Cut the Base:
Start with a large sheet of melamine or MDF.
Use a compass (or string and pencil) to draw a 52-inch circle on the board.
Cut out the circle carefully using a jigsaw or circular saw. Sand the edges slightly to remove rough spots.
2. Create the Sides:
Cut strips of melamine or MDF about 2 to 3 inches high. The height depends on how thick you want your tabletop to be.
Calculate the perimeter (52 inches × π = ~163.36 inches) and ensure the strips are long enough. You may need to connect a few pieces.
3. Attach the Sides:
Carefully bend and attach the melamine strips around the circular base. Use screws or clamps to secure the strips, ensuring the sides are flush with the base.
If the melamine doesn’t bend easily, make shallow cuts on the backside to allow for flexibility. Alternatively, use flexible plastic or PVC for the sides.
4. Seal the Mold:
Use silicone caulk to seal the inside seams of the mold to prevent resin from leaking.
Smooth the silicone bead with a gloved finger or caulking tool. Allow it to cure fully.
5. Apply a Release Agent:
Coat the inside of the mold with mold release spray or painter’s tape to make demolding easier. Melamine is naturally non-stick, but a release agent adds extra protection.
Tips for Success:
Support the Base: Use additional boards under the mold to prevent warping from the weight of the resin.
Reinforce the Sides: Clamps or bracing around the mold will help maintain the shape during the pour.
Reusable Option: If you plan to make more tabletops, consider using HDPE (high-density polyethylene) sheets for the mold, as resin won’t stick to HDPE.