Using resin molds is fun to make resin crafts and jewelry. You can make everything from man cave coasters to boho earrings. I can’t think of a better day than that. Until it isn’t that amazing day. Because sometimes epoxy sticks to your mold and won’t release. Which then makes you google, ‘Why is resin sticking to my mold?’
Hi. 👋 I’m Katherine, and I’m going to help you get out of this mess.
Here are reasons why resin is sticking to your mold:
Reason 1: Your silicone mold is at the end of its useful life.
Unlike TSA check-in lines, resin molds don’t last forever. They will dry out, get brittle, and tear with use. It would be great if they lasted indefinitely, but they don’t.
⭐️ BONUS: Here’s what you can do to care for your silicone molds to make them last longer.
Reason 2: You didn’t use a mold release.
Mold release helps resin castings pop out easily and prolongs the life of your mold.
But really, do I need to do that?
⭐️ BONUS: Here are three reasons why I always use resin mold release.
Reason 3: Under-mixed resin stuck to the mold.
Be sure to scrape your mixing utensil and the sides of your mixing cup several times while mixing. This ensures your resin is thoroughly mixed before pouring into the mold.
⭐️ BONUS: Learn how to mix resin in 5 easy steps.
Reason 4: You’re using a torch to remove bubbles.
Using fire to pop bubbles is all fun and games until your mold gets hurt.
💡 Pro tip: Don’t use a blow torch for snow removal either.
Excessive heat will melt your mold and cause the resin to stick in places. Use a heat tool instead.
⭐️ BONUS: Learn how to use a heat gun with resin.
Reason 5: You’re using molds that aren’t meant for resin.
Candy molds? Candle molds? Concrete molds?
Yeah. They might not work for resin. I know because I’ve tried.
⭐️ BONUS: Here’s what happens when you use resin in a soap mold.
Reason 6: Your resin is too hot.
It’s normal for resin to get hot when mixing. But, too much heat can melt the mold, sticking your resin to it.
⭐️ BONUS: Here’s another reason why you don’t want your resin to overheat.
Reason 7: Your silicone mold isn’t fully cured.
If your mold has spots of uncured silicone, the resin will stick in those places and tear when demolding. This most commonly happens with tin-cure silicone molds.
⭐️ BONUS: Learn how to use silicone putty to DIY resin molds.
Frustrated with your results when creating with epoxy resin?
It’s why I wrote the ebook Resin Fundamentals. I’ve condensed my 17 years of resin experience into an easy-to-read PDF book. Go from confused to confident with resin in only a couple of hours. Buy a copy now, and a PDF download link arrives in your email inbox in minutes.
Unpublished Blog Posts of Resin Obsession, LLC © 2023 Resin Obsession, LLC
If polyurethane moulds stick, pop it in freezer for about an hour.
Hi. Is there a U.K. outlet for you products?
I ask because its to far to ship stuff like resin across the pond.
if you don’t can you recommend a make that I can get in the U.K.
Hi Tom, I’m afraid we don’t have a retailer for the Resin Obsession resins in the U.K., but we can ship you many of our other products.
Thanks, Katherine! I haven’t encountered any of these problems but now I know how to avoid them. You always have the best tips!
Thanks Alice. 😉
Does anyone know how to get the silicone particles off of resin? My mold got stuck and ripped but I would like to try to salvage my project. Help :(((
Have you tried washing your resin with soap and water?
Katherine, I did a large pour of 20 small molds. The resin was old I now believe? It never really hardened and its 72 hours now. Still dripping and sticky at best. I have resigned myself to “letting go”, but, not sure how to get all this sticky, half cured resin out of all the molds without ruining the silicone molds. Please advise. Sticky in NY. 😉
Hi Clair, I’m not sure there is a way you can save your molds in this case. This article might give you some ideas: https://resinobsession.com/resin-frequently-asked-questions/how-to-fix-sticky-resin/
Having similar issues with the resin sticking to the molds. Had 2 different sets tear because resin stuck. Used a release spray. What else could be done to prevent this from happening again as all of my molds are new???
Thanks.
Hi Lisa, what release spray are you using?
My resin sat for 46 hours. Has not hardened or cured. Used mold release. Should I stick in the freezer?
Hi Rebecca, if it’s still liquid, I would not put it in your freezer.
For resin hair clips will they melt or get soft of they are worn in the outdoor?? I just started making some last week but wanted to make sure before selling them. I know that the resin letters can get soft in direct sunlight. Any tips for the resin Hairclips??
Hi Tenecia, you’re right to be concerned about your resin hairclips bending. Some resins, even when fully cured, can be bendable. For hairclips, I like to use the Resin Obsession super clear resin. It doesn’t soft with body heat and cures very durable! You can buy it in several sizes in our store here: https://shop.resinobsession.com/collections/resin/resin-obsession-super-clear-resin
How do you get the silicone mold residue off of my project piece?
My mold tore and left a long patch of gummy residue.
I know the mistakes I made, but would like to save piece.
Thank you
Hi Kathy, you can try a product like ‘goo gone’ to see if that gets off the remaining residue.
I burned my mold with a torch and it tore when I demolded, and now I have silicone stuck to my project. How do remove?
Hi Cris, you need to manually remove as much as possible, then sand the rest off.
I am using a tin silicone to make a mold of an epoxy resin piece that has been polished to be glass smooth. When I demold the piece however, the some of the silicone is stuck to the part and rips off. I am confident I mixed the silicone well, I have also made this exact same mold before and it worked great. Why could this be happening? I was thinking that many be there is something wrong with the surface of my part? But when I try I clean it the same thing happens. What should I do?
Hi, you need to apply a mold release to your model before adding silicone.
Hey Katherine,
I hope you can help!
I need to use a plastic mould for a glass finish on my resin. But it’s taking forever to get it out of the mould. I can’t use the release spray as it leaves tiny bubbles on the piece and I can’t use a silicone mould as it creates a frosted finish.
I’m pulling my hair out. Please help!
Hi Natalie, it sounds like you might be using a mold that isn’t meant for resin.
Oh also… I need to make a 100.
I had bought some silicone molds for jewelry on etsy. I added some mica powders and used the hard uv resin with a uv curing lamp i had bought from epoxy resin jewelry.com. However, when i demolded part of the back was still left behind in the mold and the back of my pieces was sticky. The fronts were all hard and good. Did i need to cure longer? I had smeared vegetable oil in the molds
I ruined 3 molds. The resin gets stuck. is there a certain resin mold you need or do you need to get a resin release
Hi Joan, you need a mold release. Try this one: https://shop.resinobsession.com/products/castin-craft-mold-release-conditioner
My resin design comes out soft and some sticky. I am getting frustrated. I use artresin because it’s non toxic. After I finish with one layer for the flowers i put it in the boiler room were it is warm. The Garage is cold. I am having suck a hard time.
Joan
Hi Joan, I’m sorry to hear this. This article will help with sticky resin. https://resinobsession.com/resin-frequently-asked-questions/why-is-my-resin-sticky/
Hello Joan,
I’m a newbie at this and I’m getting frustrated. I finally succeeded my 3d flower but I overheated my mold and now it’s torn. How are you suppose to remove tge bubbles from the sides?