Using Clear Resin in your IOD Moulds with Confidence

Recently, there have been a few instances where some of you are having issues with using clear resin (slow set) in the IOD Moulds. The following tips are to help you with any struggles and to let you know that you're not alone - I too struggled with certain aspects of using a clear resin.

 I’ve been an Iron Orchid Designs (IOD) stockist since the very beginning and I’ve used the Alumilite Amazing Casting Resin (finishes white with a 10 minute set) more times than I can count - but I’ve never used a clear resin (of any kind) until this year with the new holiday release moulds. 

There are many different companies that make a clear resin and earlier this year, I came across the Canadian company, Magic Resin. I always try to source Canadian products if available, but with any new product I carry here in the store (or online), I always test it first thoroughly. If I don’t love it - I can’t in good faith - sell it. I initially purchased their Table Top Epoxy for another project I was working on (a thin pour) and I was very happy with my results. 

So, when the new moulds came out for this holiday season just ‘wanting’ a clear resin pour, I went back and purchased Magic Resin’s Art & Craft Epoxy. This specific formula is made for deeper pours (up to 1/2” thick at a time) and therefore works perfectly in the IOD Moulds. 

This is what I’ve learned so far…

The ambient temperature in my craft room (according to the Magic Resin website/directions) should be between 22 & 24ºC (71 - 75ºF). I’m not gonna lie - that is WAY too warm for me so I’ve created a little area with a heater for doing my clear resin pours. 

It’s also important to make sure the resin itself is warm enough to flow freely. I place my bottles in warm water for a while before use otherwise it’s very thick/glue like consistency is very hard to work with. Failing to warm the resin bottles before combining creates another issue, they don’t mix properly. Even after the recommended 4-5 minute stir… they had apparently not combined well enough when cool and therefore never set up properly. Those castings are still somewhat flexible at best or have sticky parts at worst. 

Also, pouring a cooled resin mix into a very detailed mould (like Angelic Tapers for example), the resin isn’t able to settle properly causing a lot of trapped air in those little details. This led me to a whole other problem!

NOTE: I tried using a resin heating mat to speed up the cure time. While it works wonderfully for cure time, it causes tiny wee bubbles to form on the face of the castings about an hour into the cure (at least with this particular resin brand and type). This is a disaster as there’s no fixing it at that point. The resin has set up enough to make it impossible to manipulate without causing even more damage to your castings. Until I do further testing, I don't recommend the heat mat.

I did a couple of pours using my embossing heat tool to burst the tiny bubbles that rise to the surface as the resin settles. This worked well but I figured the torch would work even better and it is a tool I’ve seen many times by professional resin artists.

Now at this point in my testing… I assumed the better heat from the torch would help bring up the bubbles from deep within my pours (I hadn’t made the cool/thick resin connection yet) so I really went after my mould with the torch. Of course, unable to bring those deep air bubbles to the surface no matter what. This was my mistake. All the extra heat I was applying caused a big problem. When I went the next day to de-mould the cured resin, my casting came out along with a strip of the micro-rim on one design and a chunk out of the tip of another. This all happened on my Christmas Tapers mould as that’s the one I really went after with the torch on this specific pour. Luckily, my mould is still useable (the damage is minor and doesn’t bother me… much). 

The torch (or any heat tool) is meant to quickly pass over the pour to burst those surface bubbles. Do NOT pause and point in particular areas as this WILL cause mould damage. Used correctly, the torch works wonderfully and is oddly satisfying. I also like it better than my heat tool as there is no ‘blowing air’ causing my resin to wave about like water. 

My biggest bubble issue - by far - was with the new Angelic Tapers mould. To begin with, Angels/Cherubs are not on my design favourites list by any means so to struggle so much with this mould was a little bit frustrating and I wanted to just give up. However, I needed a solution in order to pass that on to you so I kept trying. I’m not sure what’s so different (detail wise) between the Christmas Tapers and the Angelic Tapers but my Christmas Tapers castings would come out beautifully while my Angelic Tapers look as if they’d been full of sand before I poured my resin. All the tiny bubbles sitting down in the mould look awful once set and even worse when painted. 

The solution was simple really. 

First of all, make sure your resin is warm before and during your pour. I set my mixing cup into a warm water bath while stirring so it didn’t cool in those 4 minutes before pouring. Room temperature should be at about 24ºC.

Pour a thin layer in the mould first. The surface tension of the dry mould is what causes those tiny bubbles and the thin initial pour helps to be able to minimize them. I used a small silicone tool (or wooden spatula) to help break free any bigger bubbles lodged in the details, then quickly passing over it with your heat source to pop them at the surface. Finally, pouring your final depth after you’re satisfied with your initial bubble removal layer. 

I actually achieved my best results by misting rubbing alcohol into the mould before pouring. This broke that surface tension in the dry mould and allowed the resin to flow freely into all the little details. I still poured a thin layer first before going ahead with full depth. 

So basically, all the issues can either be attributed to too much heat in one area and not enough in another. Keep in mind that all my experimenting has been done with this one brand of resin so you'll have to experiment with your own brands. I prefer the low (virtually no) odour from the Magic Resin’s Art & Craft Epoxy than the strong odor I have found with some other brands.

Have fun creating! Using resin is a wonderful alternative to clay when wanting to create beautiful castings. The clear castings open up a whole new world of possibilities with our beloved IOD Moulds!

If you'd prefer to watch a video tutorial on my process, please head over to my YouTube channel below.

**Please ensure you follow all safety precautions recommended by the manufacturer of the resin you choose.