Resin molds can be expensive. They are convenient for pouring but they can run upwards of $30 for one mold with uniform, basic shapes. I love collecting rocks and I was certain I could create a sea-glass looking resin stone with my own custom mold. I scoured the internet and found two methods for creating my own resin molds.
To create silicone resin molds, you only need 100% silicone caulk and Dawn dish soap or 100% corn starch. The dish soap molds are more flexible & will take on the finish (glossy or matte) of the object they are molded with. They also have a strong odor for around a week that is like concentrated vinegar. The corn starch molds are more firm in texture & you need to wipe them out after casting your object but they have next to no odor in comparison. Both types of mold show a great amount of detail and are exactly what I was looking to create.
Dawn Dish Soap Method
- Wax Paper (to set the molds on to cure)
- Large Glass Bowl or Container for mixing
- 1/2 large bottle Dawn Original Dish Soap
- 1 tube GE 100% Silicone (#1)
- Caulk Gun
- Objects to Press
How to Make the Molds:
- Fill bowl 3/4 full of hot water
- Add a large amount of Dawn dish soap (I used 1/2 of a large bottle)
- Dispense the tube of silicone into the soapy water
- Cover your hands with Dawn and start grabbing the caulk together. Knead/work the silicone into a ball shape. After a few minutes of kneading, the ball will begin to firm up. I used a lot of soap and mine started to harden pretty quick.
- Form mold(s) to the size you want. Before pressing your mold object into the silicone, dip it into the soapy water so it is easy to remove. The silicone smells STRONG, like concentrated vinegar. The molds will hold this smell for a couple of days.
- Press mold objects into silicone–try to form your molds so that they are deep enough for the object. You don’t want a thin front to the mold (the bottom from your view.) Also try to press the object in straight or you will have resin pouring over crooked sides when you fill it.
- Allow mold to firm for 2 hours.
- Remove mold pieces carefully. Gently bend the sides around the piece & the sides of your new mold. Wipe off excess soapy water and allow the mold to dry off thoroughly before filling with resin & using.
Corn Starch Method:
- Paper or Wax Paper to set molds on to cure
- Large Container for combining (I used the lid from a disposable baking pan)
- 100% Corn Starch
- DAP 100% Silicone (white)
- Objects to press into mold
- Old bank card for combining **You are not mixing the corn starch & silicone like a baking recipe. You squirt the caulk onto the pile of corn starch and start moving it back & forth and smooshing it into the corn starch. Once it starts to firm up, knead it with your hands. If you don’t leave chunks of caulk in the corn starch, it can be reused for the next mold**
How to Make the Molds (made individually):
- **Depending on the size of your mold, you will use different amounts** To your container, add 1-2 cups of corn starch and 2-4 releases of caulk
- Begin moving the caulk back & forth over the corn starch. Once it firms up enough, begin kneading it with your hands. Keep your hands coated with corn starch.
- Knead until the mold material is no longer tacky. You will work it for awhile—every time you think it is good, you will knead it one more time & you will feel stickiness. Keep at it until it isn’t sticky.
- Form the mold into a disc/round shape that is deep enough to hold your mold object.
- Press in the object to be molded (try to make it level)
- Let cure for 1-2 hours
- Remove object from mold & wipe out excess corn starch
I have only used my molds for epoxy resin but I am sure they can be used with other materials. I have been using them frequently. Both types are great. I have only had issues with tearing or holes in my dish soap method molds. The easy fix to that is to patch it with a little 100% silicone caulk on the outside of the mold (so you don’t lose your shape) and pat it down with a little corn starch on your finger. I am working feverishly to perfect my faux-sea glass and these molds are a great help!