Even after working with resin for over two and a half years, I still consider myself a novice. It’s amazing, horrible, magic, fickle, wonderful and frustrating to work with.
Room too cold? Lots of bubbles will be introduced during mixing and the resin takes much longer than normal to cure. Room too hot? Resin will cure too quickly. Evaporative cooling in the house turned on? Moisture in the air can ruin all your hard work, causing ripples in the finish. Didn’t measure accurately enough? Didn’t mix the resin long enough? Dust? Cat fur? Clumsy hands? Dropping a piece of paper towel on the batch of just-poured resin? All great ways to ruin your new pieces – trust me, I’ve done them all!
In addition to all of that fickleness, there’s also the problem of choosing the best type of resin for your purpose. There are many different types, from epoxy to polyurethane to UV resin and many more. The right resin for the job is step one in creating an amazing piece of jewellery.
This is part one in a series of blog posts setting out everything I’ve learnt about resin over the last two years.
For doming (creating a bubble-like effect over glitter, much like my stud earrings), I use Ice Resin.
Ice Resin is a two-part, jewellery-grade epoxy resin which is mixed in equal parts. It sets hard, but when worn directly against the skin, it warms and can become bendy. This makes it unsuitable for items like rings and bangles (stay tuned for future blog posts in this series where I talk about the resin I use for these pieces).
Accuracy is the most important thing when you're using resin. If you don't measure and mix appropriately, your resin may not cure completely - or at all!
Measuring and mixing
Ice Resin can be very prone to bubbles during the mixing process. There are a few ways to minimise the amount of bubbles introduced at this stage.
Warm your resin in a bowl of hot water prior to use. I place the resin bottles in a medium sized plastic mixing bowl filled with hot tap water. I wait five minutes or so, then replace the water with more hot tap water. After a further five minutes, your resin should be ready to measure and pour.
Make sure the lids of your resin are never submerged in the water. If water gets in to your resin it’ll need to go in the bin.
Measuring your resin as accurately as possible is so important, and something that comes with trial and error. It is recommended that you measure your resin out in two separate mixing cups before combining in a third cup to mix. I don’t do this. Instead, I measure both parts in one medicine-type mixing cup and mix it together.
HOT TIP: if you are using a measuring cup with the measurements indented into the plastic, mark the relevant measurements with a marker prior to pouring. As you pour the resin parts into the cup, you’ll see the indentations are filled in with resin and basically disappear, making it very difficult to see how much you’ve poured.
It’s important to stir the two parts very thoroughly, but not at all vigorously, as this can introduce bubbles. Stir it for a good few minutes, scraping around the sides and bottom of the cup. As you mix the resin you’ll see it go from cloudy (pic 1 below) to clear (pic 3 below).
Once it is completely clear with no striations (wiggley bits in pic 2 above) it’s ready to go. If there are a lot of bubbles, let the resin sit for a few minutes and they should rise to the surface so you can scrape them out.
When pouring resin, you’ll want to check on your pieces often for the first hour or so. Additional bubbles will form during the chemical reaction that causes resin to cure. You can pop the bubbles in a number of ways. I run a lighter or gas gun quickly over the tops, but you can also gently blow on them through a straw if you’d rather steer clear of fire.
Resin takes around 24 hours to cure – sometimes more, sometimes less, depending on a range of factors.
Out of the resins I use, I must say Ice Resin gives me the most grief, but great results. The resin comes in two parts: the resin part is tinged blue and the hardener part is tinged yellow. When mixed they should be crystal clear. I have had a few batches of resin arrive with the hardener a much darker yellow than it should be, which causes the final product to also be tinged yellow. This resin can only be used if you’re going to colour it further. I assume the yellowing happens over time, so figure it must be old stock.
Towards the end of last year I ordered large bottles of resin to make sure I didn’t run out right when market prep and online sales were hitting their peak. When I opened the bottles to use for the first time a few days before our biggest market of 2017, I encountered a brand new problem: crystallised resin! I thought I was going to have to waste the time sending the resin back and getting it replaced – valuable time I didn’t have at the busiest time of year.
After some googling I discovered the answer was actually pretty simple – heat. I grabbed out my slow cooker, filled it up with water and put it on as low as possible. I then double Ziploc-bagged the resin bottle to keep the water out, submerged it in the water and put a plate on top to stop it floating. I left it in there for close to an hour, checking on it regularly.
At the end of it, the resin was back to normal! Christmas was saved!
Not curing, curing soft
This is most likely due to resin either not being measured accurately, or not being mixed thoroughly. Try again!
Part 2 of this "everything I know" series will focus on polyurethane resin, which is best used for rings and bangles.
Let me know in the comments if you have any questions or feedback!