Image by KengLye
Many people get confused between epoxy resin and polyester resin. So here’s a quick summary to set things right.
Clarity
Epoxy resin gives better clarity compared to polyester resin. While epoxy resins are not crystal clear like water, they still have more clarity compared to the yellowish tinge found in polyester resins.
Scent
Polyester Resin has a very strong smell and is often hazardous to inhale in large amounts. Epoxy resin has almost no fumes or smell which makes it more pleasant for you to work with it. However, it is important to have proper ventilation while working with both epoxy resins and polyester resins.
Price
Due to its formulated requirements, epoxy resin is generally more expensive than polyester resin. There is a significant price difference between both of them and if you are into jewelry making and craft, it is a more popular ingredient to use because of its lower cost.
Health
Polyester resins are made from volatile organic compounds and styrene, an ingredient that is said to kill brain cells. Epoxy resin is a healthier option for you to choose and this is why it is the go-to material for jewelry makers.
Hardness
And lastly, epoxy resin is harder than polyester resin and more resistant to wear, cracks, peeling, corrosion and damage resulting from environmental and chemical degradation. Polyester resin is more fragile and flexible which makes it easier for you to do casting and mold.
Craftiviti 
Hi, I would like to do adults hands casting. I’m keen to buy but new to this topic so I need suggestion what to buy and diy instruction. Please help.
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Hi there Vani. Thank you for writing to us. Hand casting is one of our popular projects. You will need the following products:
To make the mold:
https://www.craftiviti.com/product/alginate-life-casting-powder/
To cast a replica of your hand:
https://www.craftiviti.com/product/plaster-of-paris-powder/
Watch this video to find out how:
Happy crafting!
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If I want to make a casting as clear as water, is there another option other than Epoxy or Polyester?
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Hi Joeri, the clearest resin we carry would be Alumilite Water Clear.
https://www.craftiviti.com/product/alumilite-water-clear/
Hope this helps and new stock is coming in soon.
Thank you Joeri
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The 3d resin goldfish image in the post above is epoxy resin or polyester?
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Hi Nicole, the clear effect from the image is made from clear epoxy resin. Polyester resin has very low clarity and does not come out crystal clear.
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I much prefer epoxy, had a brief experience with polyester back when I started working with resin. I have to say, I really don’t like it… I thought I’d give it a try because it is a lot cheaper than epoxy resin, and now I know why.
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Thanks for the feedback. It is true that Epoxy Resin has a better and finer quality to polyester resin PLUS the high point that Epoxy is not toxic and does not have pungent fumes. However, it’s always good to try, explore and know at the end, what suits you better. Keep on crafting!
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Hi, I am curious … this article seems to contradict everything i had read elsewhere, and my own experience.
In most articles about this topic it says that Polyester resin dries clearer, harder, and is more resistant – such as this article https://www.resinobsession.com/resin-frequently-asked-questions/what-kind-of-resin-should-i-use
In my own experience with Epoxy, it can sometimes cure soft and dull over time, so I want to find a better alternative that is hard wearing and keeps its shine, etc. How do i know what sources to trust? How can we get the best results with epoxy resin?
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Hi Dylan, thanks for reaching out to us! This article was written with our experience and what we’ve learnt in mind. Of course, this can differ for everyone because despite general consensus on matters, we’ve realized that brand and type (whether it’s 1:1, 2:1 or 3:1 for resin to hardener; flexible or hard) of epoxy resin used does effect the outcome. The sources you should trust should be the ones that align with your own experience and understanding. As for how you can get the best results with epoxy resin, finding the right brand and type to work for specific products would be the key (ie: 1:1 epoxy resin for alcohol ink coasters, 2:1 epoxy resin for canvases and boards). Hope this helps! 🙂
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