Over the past few days, I made a batch of coasters using a method I don’t usually try. I split 16 ounces of resin between 9 molds, then decorated four of them with glass chips and four of them with some seed beads. I also made an experimental one with white and black pigments for my eldest child in an attempt to create a “galaxy” look. I also made a few beads while I was at it. I normally wait longer before I decorate, but with this batch, I decorated within 20-30 minutes of pouring and then topped off all of the coasters with another batch of resin. Maybe that’s not a long enough waiting time.
The resin yellowed as it cured. I’m not sure if this was because of the amount I poured (I normally use smaller layers) or the amount of time I waited (or didn’t wait) between layers of resin. I’ve only had this happen once or twice in the past.
But that wasn’t the worst part. After demolding, I noticed that the molds where the seed bead coasters were now have little indentations anywhere the seed beads were. That pretty much ruins the mold, so I had to order some new ones.
I’m guessing the resin got too hot when it was curing. The type I have been using (Envirotex Lite) thickens pretty quickly, which can make it difficult to get into the tiny bead molds if you’re slow. I sent an email to the resin makers to see if they can tell what I did wrong. Hopefully it’s something straightforward.
Note: I heard back from the manufacturer of the resin a couple days later. They recommend a different type of resin for molds/ thicker applications.
“Our Envirotex lite is intended for coating table tops, bars, chairs etc… We do not recommend for filling molds. Envirotex can be poured at a max depth of 1/8 inch, any more than that causes a heat reaction. We recommend waiting 6 to 8 hrs in between coats. We do have a two products that we recommend for molds, Easy Cast. Polyester casting resin. Both products can be found on Amazon, Michaels Craft store, Hobby Lobby and Joann Fabrics. I hope this information helps and if you have any further questions please feel free to ask.”