Molds for resin – Your burning questions answered!

Your questions about molds for resin answeredYou’ve decided you want to make resin crafts, and now you find yourself with questions about molds for resin. Can anything be used as a resin mold? Are resin molds expensive? Will I need to do anything special once my resin comes out of the mold?

It’s okay. I’ve been there. When I first started creating with resin (it’s been almost 15 years ago!), I had a lot of questions too. Let’s dive into what you need to know when you use molds for resin.

Why use molds for resin?

pouring resin into a silicone mold

Let’s start by talking about what resin is. It is a liquid that, when activated (either by adding catalyst in the case of two-part resins or UV light with UV resin), will warm up and form a solid mass. That means you activate the liquid, then pour it into a mold. As it solidifies, it will take on the shape of the mold and keep that shape after it cools. That’s why resin can help you make coasters, jewelry, paperweights, and more.

What makes a good mold for resin?

You might be thinking that any vessel will make a good resin mold. Unfortunately, it isn’t that simple. There are a few key things you need to know about choosing molds for resin.

The mold material needs to be able to take heat.

Because the resin heats up, there is a risk of melting your mold or the resin starting a fire. That’s why styrofoam containers and paper cups don’t make suitable molds. Instead, it needs to be material, like silicone, that can take heat as high as 200F.

The mold material needs to flexible.

demolding resin coaster from geode silicone mold

You can pour resin into a glass baking dish, but what you will find once the resin cures is that the resin has done a great job of sticking to the dish. Of course, because the glass is also rigid, you won’t be able to flex it and pop out the resin.

But you will have a beautiful dish of resin.

The mold material needs to be thick enough to release the cured resin.

You might be tempted to pull from your stash of plastic candy molds to make resin crafts, but I will save you the disappointment. The resin will cure but stay forever stuck in your mold. And the same applies to candle molds. You can see what happened when I try to form resin in a soap mold. Hint — it didn’t go well.

So now that we know what doesn’t make suitable molds for resin, what should you look for?

The easiest place to start is with molds designed for resin. We’ve got a bunch of them in the Resin Obsession store. Here are some of our customers’ favorites.

The molds we sell are made with silicone or polypropylene plastic. Both types of molds are flexible and release resin easily. Not only do we have them in a bunch of different shapes and designs, but they are meant to be reused.

How do I know if my resin molds will make a glossy finish?

The BIG rule you need to know about resin molds is that whatever the finish on the mold, that same finish will impart onto your resin castings. That means if your mold has a shiny molding surface, your resin will cure with that same shine. The opposite of that is true too. A frosted surface mold will make frosted surface resin castings.

What if my molds for resin don’t have a shiny finish?

Don’t worry, you can still use the mold. If you want your resin to have a shiny finish, you will need to take a few extra steps to make the resin shiny once it comes out of the mold. You can do that by using resin like a glaze and applying a coat to your flat surface to make it shiny. If your surface is curved or detailed, you can get a shiny surface easier by using a couple of layers of resin gloss spray.

Can you use silicone baking molds for resin?

So, while the easy answer is yes, you may not be happy with the finish. Baking molds usually produce a frosted or cloudy surface, requiring extra steps to give the resin a glossy finish if that’s what you want.

Can I make my own molds for resin?

silicone putty

Yes, you can! The easiest way to do this is to use two-part silicone mold putty. Simply ‘eyeball’ an equal amount of the two parts and blend together with your hands. Then, form the putty around the item you want to mold.

Pro tip: If you want the resin to cast shiny with your DIY molds, then make sure the thing you’re molding also has a glossy finish.

How do you keep molds for resin in top shape?

Using a resin mold release protects your mold against micro tears and makes it easier for resin charms to pop out. In addition, you won’t have to twist on your mold as hard to demold it. I’ve got other tips too on caring for resin molds.

What resin should I use for my resin molds?

You will get the best results by using a casting resin. Casting resin and molds for resin go together like peanut butter and chocolate! Casting resins mix in a thin consistency, which allows bubbles to escape quickly. That means you can pour them in deep layers or intricate patterns with less of a chance that you will trap bubbles.

Best casting resin for small pours

Resin Obsession super clear resin
Mix between ½ ounce and 3 ounces at once
25-minute working time
Cured to demold in 8 to 12 hours

Best casting resin for large pours

Resin Obsession deep pour resin
Mix between 3 ounces and 3 gallons at once
30-to-90-minute working time
Pour up to two inches thick in one pour

Can I put my molds for resin in the oven?

Say what? Are you in a hurry to cure your resin? You can put resin molds in an oven to speed up curing. Set the temperature to 150F and mix and pour your resin as usual. Insert your mold in the oven for five minutes, then check. You want to make sure you aren’t melting your mold (especially plastic molds), and your resin isn’t hot and smoking. If things look good, then turn the oven off and let it cool. You can repeat this process if you’re pouring another layer.

Important safety tip — only try this with an oven that you won’t use for food again. An inexpensive toaster oven works great for this.

Want to make something with resin molds but hesitant to get started?

Then you will want to get a copy of my ebook, Resin Fundamentals. I’ve taken my almost fifteen years of resin experience and condensed it into a downloadable book that shares the essential details of ‘what you need to know’.  Buy now, and you have a copy to read in minutes!

Unpublished Blog Posts of Resin Obsession, LLC © 2021 Resin Obsession, LLC

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