This is an easy walk through on how to use epoxy with silicone molds. I have been using epoxy for sometime now and wanted to share some tips and tricks I have learned.
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Step 1: Gather Materials
Silicone Mold - halloween themed or whatever is your fancy
Disposable Plastic Cups - needs to be plastic and wax free
Stir Sticks (wooden popsicle sticks or plastic disposable forks)
Heat Gun or Butane Torch (if you do not own one then you can get away with not doing this step, this only helps in the curing process to remove bubbles from the epoxy)
Epoxy, I use Glaze Coat by Famowood
Latex Free Disposable Gloves (recommended)
For Magnetic Epoxy Skulls
Drill Bit - same circumference as the magnet or slightly larger Quick set Epoxy, or super glue
Note: I personally do not use the silicone mold again for ice or food or what ever it was originally intended for. Food safe or not I just wont risk it.
Step 2: Measure and Color
This brand of epoxy requires a 1 to 1 ratio mix. I used the large red cups to do a 1 to 1 pour and followed the instructions on how to mix. For this brand to save on the amount of waste you can actually use just two cups. I usually pour the epoxy resin into the hardener cup mix and mix for 10-14 mins by hand or, I use a plastic fork that fits into the chuck of my drill and slowly turn it. It is a lazy way and might add to the amount of bubbles in the mix, but you can get those out with the heat gun and time. From the red cup I pour an even amount into the smaller white cups.
Then add the color of your choosing, you can find many colors online. You can also use ground up sidewalk chalk (color and quality is dependent). Stir throughly and add more coloring until it is to your liking.
I used wooden "tongue depressors" or popsicle sticks for this but, usually I use plastic forks, it has less of a chance of specs getting stuck in the epoxy.
Step 3: Pour and Set
Depending on the instructions and what your ratio is you have a limited time to pour the epoxy before it starts to harden/set. You will know it will be setting when it starts to thicken up and move from a thick syrup to a molasses, then like sap.
I like to pour with a thin line this helps with taking some of the bubbles out. You can do a multi color pour starting at the same time from opposite ends, or whatever sparks your creativity!
I used some of the left over to pour legos in my lego mold. I have a special project I am planning for this I will post once it is complete.
Let the molds sit in a dust free area and wait till the instructions or at least 8 to 12 hours. Over night is the best for it to fully set. Some epoxies react differently to humidity and temperature. For this pour it was 72 degrees fahrenheit and ~25% humidity. You will want to do a bubble watch every 15 mins.
Bubble watch will help with the finish. This epoxy naturally pushes some of the bubbles out, but heat will speed up this process. Using heat is bittersweet, if done right it improves the finish, if done wrong it will ruin the piece. You can use a heat gun or a gas torch. Both work about the same. The convenient use of the heat gun is that you can get consistent temperatures. I use one where I can set the temperature and fan speed, it is pretty close to the actual read out too. If you hold the heat in one place you could "burn" / harden the epoxy faster in one spot, and that will affect the rest of the spot and cause a brown or yellowing effect. Lightly come in and out with the heat watching the bubbles and speed of the bubbles coming to the top. There are plenty of youtube videos, forms, and how to's on how to do this too.
Step 4: Fully Cured
Once the epoxy has fully set, pop your new creations out!
If you notice a little stickiness just let them set out a little longer. If it is the inside of the mold then pop them out of the mold and let them air out outside of the mold.
Step 5: Magnetic Skulls
If you want to add magnets to the back then find some high strength magnets and a matching drill bit. Mark off your drill bit with tape to the depth of the magnet and drill into each of the molds until you reach the tape. Mix some 5 minute epoxy or quick epoxy or super glue. Use a cotton swab with the end pulled off and swab into each of the holes drilled. Be sure to use just enough or when you push in the magnet you will get some overflow or push it all to the bottom having the magnet stand off to much and not flush. Place all the magnets into the holes and if they need a little push use a piece of scrap that you are okay with getting epoxy on or throwing out.
Step 6: Finished
Once you let the magnets sit in the fast set epoxy or superglue they are ready to go. You can place them on your door (if metal) or refrigerator, or anywhere you want! Tic tac toe is always a fun game if you made enough too!
I hope you enjoyed this quick and easy tutorial!
If you have any questions leave a comment! Thank you!
Participated in the
Halloween Contest 2019