Craft Resin FAQ: UV Cure or Epoxy? Answered by Project Type
Every craft maker eventually hits the same wall: a project calls for a clear, hard, glass-like finish, and the two candidate materials — UV resin and two-part epoxy — behave so differently in practice that picking wrong means redoing the piece. Here are the specific questions that come up most. Q: I'm making resin coasters with dried flowers pressed flat inside. Which resin? Epoxy for anything beyond a very thin coaster. A standard coaster thickness exceeds UV resin's practical per-layer cure depth of roughly 3–5mm, meaning a UV approach requires several sequential thin pours with a cure step between each — workable, but slower and more labor-intensive than a single self-leveling epoxy pour that fills the whole mold in one step and cures overnight. Q: I want to encapsulate a photo inside a resin pendant without the image shifting during cure. What controls that? UV resin is the stronger choice here specifically because of its on-demand cure — you can lay the photo, check its position and orientation under normal light, adjust if it's crooked, and only trigger the cure once satisfied. Epoxy begins curing the moment it's mixed, and a photo can drift slightly as the resin settles and levels before it gels, which shows up as a slightly off-center image in the finished piece. Q: I'm building a large resin art panel with swirled pigment colors. Does layer thickness matter here too? Yes, and this is squarely epoxy's territory. Large panels require deep, single-pour capability that UV resin's shallow cure depth can't match, and epoxy's slower cure gives pigments time to swirl and blend naturally under gravity before the material sets — an effect that's difficult to replicate with UV resin's near-instant cure, which locks colors in place the moment the lamp is triggered. Q: My glitter keeps settling to the bottom of my UV resin bezel before I can cure it. What's going on? This is a viscosity and cure-timing issue, not a material defect. Low-viscosity UV resin gives glitter and fine inclusions time to sink before the lamp is applied if there's any delay between placement and cure. The fix is triggering the cure promptly after arranging inclusions, or working in thinner layers so gravity has less time to act before each layer locks in place — building the piece up gradually rather than trying to suspend everything in one pour. Q: Can I mix opaque pigment into UV resin the same way I would with epoxy? Only with real limitations. UV resin depends on light penetrating the resin to trigger cure, so heavily pigmented or opaque UV resin can fail to cure through its own thickness — the surface hardens while material beneath stays liquid. Epoxy has no such constraint, since its cure is a chemical reaction independent of light exposure, making it the more reliable choice whenever a project calls for solid, non-transparent color mixed throughout a deeper pour. Q: How do I stop my epoxy pour from yellowing months later? Standard aromatic epoxy…