Can anyone tell me where I have gone wrong in casting epoxy resin?

Question

I have recently started casting epoxy resin, wanting to make some adorable sticker resin charms for myself.

To give you a better understanding of my dilemma, I shall go step-by-step of what I did when casting resin, as it is very difficult for me to go straight to the problem.

First, I mix equal parts of the resin and hardener (Easy Cast Epoxy Resin) and slowly stir them for five minutes, before letting them sit for another five minutes.

Next, I pour them into the molds (Padico brand) and waited until the resin mixture is slightly tacky before putting my resin in.

I then waited for another 30-45 min for the mixture to turn very tacky, so the glitter (I used nail glitter, not fine glitter powder) won't dispersed, before taking a generous amount with a spoon and dumping them into the molds with the mixture in them.

However, some of the glitter turn darker and clumpier, and uneven since I tend to pile a lot on top of the resin. And I finally pop them out (this is the dilemma), there are always parts of the resin piece that don't have glitter, even though I have cover them with glitter.

I am very frustrated right now, and if you perchance have a solution to this irritating problem of mine, it would be very helpful since I am still a newbie.

I just hate seeing the resin pieces come out with patches of colour (glitter) missing from the background, but I don't know what I am doing wrong.

Please help! Thank you >_<

Answer 1

I'm not exactly sure what you're doing after piling the glitter onto the still-tacky resin surface, but there are a few things I think could be problems:

...when mixing parts A and B of clear resin, it's not necessary to stir *slowly* or for 5 minutes....it's usually stirring fairly rapidly (although without raising the stirrer into the air each time which will whip extra air into the resin) and for 2 minutes each in 2 sequential containers

...resin is usually poured into molds, or otherwise used, right after mixing not after waiting (if you're doing that to prevent natural bubbles, there are other ways to prevent and get rid of them)

...you said: ". . .letting them (mixed A + B) sit for another five minutes.

>> Next, I pour them into the molds (Padico brand) and waited until the resin mixture is slightly tacky before putting my *resin* in.<< I then waited for another 30-45 min for the mixture to turn very tacky (before adding glitter). . . " I don't understand the part between the brackets >> <<. What exactly did you pour into the molds if it wasn't the mixed resin??

...you then said that after the 30-45 minutes of sitting --the 2nd time the mixed resin had sat-- you dumped in glitter... was that the last thing you did? or did you then cover the glitter with more resin as would be normal?

(and if you didn't add more resin, the "very tacky" resin you dumped the glitter on probably wasn't liquid enough or still adhesive enough to grab onto much of the glitter... and if you did add another layer of clear resin on top of the glitter, the poured resin would have disturbed the heavy layer of glitter you used and created uneven areas)



Often what's done in situations where a *layer* of glitter is wanted in a casting, the glitter is mixed into a small amount of clear resin separately then added as a separate layer somewhere in the casting once the previous layer has firmed up a bit (or that glitter-mixed-into-resin is just used as the last layer which will end up being the back side of the casting).

Or often glitter is just mixed into all of the resin, or most all, then poured (and perhaps something is added on top of that when tacky and a final thin layer of clear resin is added to create an even surface, etc).

But rarely, something like what you did is created though this one uses clunky flake glitter and looks different.**



I don't know why some of your glitter got "darker" though the clumpiness would be explained by the thick layer of glitter you used, and/or not mixing the glitter into resin separately if you want it to be only a layer of glitter. The darkness may only be an effect of the clumpiness (shadows, etc), for example.



If you want to read a lot about using various kinds of art/craft resins (including the "tweaked" epoxy resin with the brand name Easy Cast, which has a few problems of its own), check out some of my previous answers here on resins:

https://answersrip.com/question/index?qid=20140118071238AAOocua



https://www.google.com/search?q=how+to+use+glitter+in+resin+in+molds

https://www.google.com/images?q=how+to+use+glitter+in+resin+in+molds



** http://resincrafts.blogspot.com/2012/07/glittered-roses.html





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Answer 2

Well, all the words describing the problem are in your excellent description and the first answer. Because of variations in temperature and humidity, the setting time varies from the perfect waiting time. Backing off a minute on the times you give should not mess up things, or 30 seconds if you are cautious.

One obvious problem is your over application of glitter and your apparent failure to tap on the mold to knock the glitter to a level layer, which you should be doing - the darkness may be due to wetting in one area and not in another. Also, tapping gently will settle the particles into the epoxy some.

Also, how are you checking for tackiness? If you are touching it with a finger tip, you are probably leaving skin oils which reduce tackiness in that area. The safest way to test is to make a separate little mold only for the purpose of testing the setting condition.

Answer 3

I think perhaps you should adjust your waiting times (there seems to be a lot and while they are nec. maybe they should be shorter) Your glitter is not sticking because the epoxy is too dry there. Think about trying a sandwich approach too- with glitter in the center...

Answer 4

Your glitter is not sticking because the epoxy is too dry there. Think about trying a sandwich approach too- with glitter in the center...