Why Does Resin Pop Out? How do I fix it? And how do I avoid it in the first place with good techniques? It can be devastating for a client to lose even the tiniest bit of their loved one’s ashes or hair or even milk from their baby’s last feed, so it’s essential to minimise the risk of your resin popping out. Last week, a very good client sent me a message on WhatsApp asking this question:
So i wanted to ask some advice because i had twice that the direct poured stone fell out of the ring…I already made a lot of jewelry, so it is not a lot but it makes me a little nervous. Do you have any advice to prevent the stone falling out of the ring…? The working conditions are good, so its not the humidity or something.
I was planning from now on to sand down the inside of the ring a little bit and then clean it with 70% alcohol before pouring but i dont know if that will be enough
So first of all, thank you so much for letting me post your question anonymously. All questions are good questions. We should always be ready to change our methods, try to learn and enhance our jewellery’s longevity, no matter how long we’ve been trading. In the past couple of years I’ve been using a couple of additional techniques that I’ve heard can help with this issue.
Why Does Resin Pop Out?
This is an experienced artist who sells a lot of pieces. She tells me that only a couple of clients have come back to her with this issue. It doesn’t sound like anything she’s doing wrong and unfortunately this is something that can happen with direct pour, also known as filling a setting with resin. Personally I’ve always preferred making a resin stone in a mould then putting the stone in a rubover setting over direct pour, and you can read more about the pros and cons here.
Shrinkage Curing
Resin shrinks as it cures – this article from Science Direct, although about polyester resin, makes a fascinating read if you have a science or engineering background but don’t worry, it’s not a recommended read! As your UV or epoxy resin cures, it’ll shrink back from the sides. You only have to fill a mould with cheap UV resin and cure it all at once to see a massive shrinkage. PLEASE DON’T DO THIS ON PURPOSE! It’s dangerous and I’ve seen resin smoke and even heard of it bursting into flames if it gets too hot. That’s why we work in thin layers with UV resin. So during the curing process the resin shrinks.
Expansion and Shrinking in Temperatures
Most materials, including plastics, expand when heated and contract when cooled due to the decrease in kinetic energy of the molecules – Quora
If your client washes dishes or sunbathes, for example, the resin in their jewellery could become hot enough to shrink. When it cools down it will move again and all of this can cause it to pull away from the edges.
Chemicals
Any chemicals have the potential to degrade the resin in your client’s jewellery, causing it to yellow or soften, making it more likely to wobble and fall out.
Water
If water somehow manages to get in a gap between the resin and the bezel cup then it can gradually exacerbate the problem over time and cause the resin to pop out. Resin is water resistant but not water proof.
How To Avoid The Issues
Scoring The Bezel
The first thing you can do is score the bezel cup, also known as adding scratches or a “key”. This texture gives the resin something more to hold onto. I like to use a pointed diamond file or the end of my curved burnisher but anything sharp will do; please be careful not to cut or scratch yourself! Also, be sure not to push too hard that you can see dents on the other side of the bezel cup.
Adding A Lip
If your bezel is thick enough, you can add a lip by scoring deeply around the edges. I like to use a tiny burr bit like this on my pendant motor and my Ayla and Hannah rings already come pre-scored and with the lip added.
Resin Quality
The brand of resin really does matter. Our standard UV resin here is fine especially if you’re learning, but I recommend Padico and I think it pays for itself because of how easy it is to work with, how much time it saves me avoiding having to top coat and I find it shrinks less than other brands I’ve tried. If you’re using epoxy, make sure the brand comes highly recommended in groups and forums and do tests with a few brands.
First Layer Clear
The first very thin layer in your piece can be clear resin, which provides a much better adherence to the metal than resin with pigment and inclusions mixed in. It only needs to be a super thin layer and you can prep all your settings up to this stage in bulk if you want to!
Care Instructions
Clients won’t normally read them but you MUST provide care info. These resin jewellery care instructions here are FREE so please download them and re-word or translate into your own language. I print them out and include them with each order but you could also add them as a page to your website.
In conclusion, if you’re wondering why does the resin pop out? Then following the above tips should help reduce the risk, but if I have a choice (a rubover round bezel cup ring, for example) I will always make a stone because it’s mechanically secured and safer. Please let me know below if you have a question you’d like me to answer in the blog.
Please note, this blog contains affiliate links, meaning I may earn a little extra income based on any purchases you make after clicking them, at no extra cost to yourself. See my affiliate policy here
Nikki