Knowing the difference between plastic and silicone molds is important to getting the results you want. Both types of molds can work with a variety of resins, but knowing the limitations of each is essential to making sure your products turn out correctly.
Here, we’ll go through an overview of both plastic and silicone resin casting molds and their pros and cons. You can use this article as a handy guide whenever you need a mold for your next project!
These reusable resin casting molds are usually made from polypropylene or polyethylene sheet plastic. They are generally made from a template and are partially flexible.
- Inexpensive. Plastic resin molds usually cost less than $10 each. (Many for under $5!) If or when you damage a mold, you’re usually not out a lot of money to replace it.
- Easier to work with. Plastic molds are a great place for new crafters to start. They are easier to demold and care for as compared to silicone molds for epoxy resin.
- Castings are not likely to be shiny and bright. The surface of the casting that is touching the surface of the mold may not be as shiny as you want once removed from the mold. You will either need to recoat with another layer of resin or cover with a layer of resin gloss sealer spray.
- Can easily be scratched. While it is helpful that the plastic is flexible, the softness makes it easier to scratch the surface. Something like a toothpick or a fingernail can leave a noticeable gouge if you are not careful.
- Difficult to make your own. Making your own plastic resin casting molds requires vacuum-forming sheet plastic around a template, which requires specialized equipment.
These reusable molds are made from two-part silicone and can last for many years if cared for properly.
- Very flexible. Silicone resin casting molds allow you to do complex castings that can be removed much more easily as compared to plastic molds.
- Custom molds. You can purchase two-part silicone yourself and mold anything you want to (assuming you have a model).
- Castings may come out shiny. I say “ may” here because the original model used to make the mold must be shiny. If it is (like with our geometric silicone resin molds), then your casting should come out just as shiny as the original.
- Expensive. Silicone molds for epoxy resin and general crafting can be two to three times the price of a plastic mold.
- Requires more care. Silicone molds must be cleaned after use and stored flat in a cool, dry area.
- May require pressure casting. Unless you’re using a clear silicone mold for epoxy resin, you might not see all the bubbles in your resin when casting it into silicone. You might need to use a pressure casting set up to make sure all your bubbles are handled before the resin starts to cure.
So which kind of resin mold should you choose?
Either resin casting mold can get you great results. Pick the style and shape you like and start creating! Resin Obsession has lots of molds to get you started, all chosen by avid resin addicts who trust them for all their crafting.
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Unpublished Blog Posts of Resin Obsession, LLC © 2021 Resin Obsession, LLC