Although you don’t actually need to seal polymer clay, sometimes you want to use a varnish or other coating to enhance the appearance or protect surface treatments. You can use a brush-on varnish (see how 41 different ones compare here) or perhaps you might want to use resin (read about that here) or something else like a dimensional glaze, floor wax, or even a glue (see here). Some varnishes might even be sticky and never fully dry. You might even be tempted to use a spray varnish, but the vast majority of spray products are a terrible idea on polymer clay and will become as sticky as a glue trap in a mouse-infested warehouse (read about sprays here). But not all. Some sprays work nicely, and I’ve found a great one for you to try! First, I want to tell you a few important things about using spray varnish, spray lacquer, and spray gloss on polymer clay.

Must-Know Info about Sprays on Polymer Clay

• Most sprays never fully dry on polymer clay. The majority of sprays will be sticky.
• Even if a spray works fine on other materials, it likely won’t work on polymer clay, which is a plasticized vinyl.
• It’s not due to the propellant. It’s because the plasticizer in polymer will also soften the vinyl-like components in the spray.
• Sprays don’t damage the polymer clay, itself. Rather, it’s the spray coating that gets sticky. Remove the coating and the clay isn’t sticky.
• Sticky sprays can usually (not always) be removed by using isopropyl alcohol, the higher the percentage the better.
• You’ll usually know right away if a spray doesn’t work. It’s not typical for them to work in the beginning and then degrade six months down the line. I generally see no change in finishes over time. (The exception being dimensional glaze, a brush-on product.)
• Humidity CAN affect the way a spray dries, making it sticky or white. If that happens, try heating your project in a low oven (200F) for 15 minutes or so.
• The clay brand matters. Sculpey III usually tolerates sprays fairly well. Fimo will make nearly all of them sticky.
• Sprays tend to be country-specific due to laws around transport for flammables. What’s available in one place won’t generally be imported to another.
• Matte sprays are generally okay. Generally, it’s the glossy sprays that are the stickiest.
• You can see how your favorite sprays rate in this article.
• The favorite of clayers for many years was a product called PYM II, and many of us still have stock on hand. But it is no longer being manufactured and is completely unavailable.
• I’ve been searching for a substitute for PYM II and have not found anything identical.
• If you need a matte spray, Helmar Crystal Kote Matte is a light fixative. (Its availability seems to be sporadic.)
• For a great high-gloss spray varnish for polymer clay, read on!

Best Gloss Spray for Polymer Clay

While PYM II was a great favorite of clayers, it didn’t have a very glossy finish. High-gloss sprays have been problematic. I have bought and tested so many of them. Every time someone would recommend one, I’d buy it, only to find that it performed poorly. I had almost given up hope.

But one day Linda Clay from Claymation3D contacted me with photos and a suggestion for a spray she’d tried five years earlier and had great results with. I wasted no time in buying that spray and I’m thrilled to report that it passed all tests with flying colors! And what’s more, it’s far better than I had hoped. This is a wonderful spray that’s available in many countries, too! I’ll also mention some other gloss sprays that I have not tested personally, but have on good authority that they also work.

Meet U-POL

This spray will be your new best friend. Seriously. U-POL is an automotive clearcoat spray (Affiliate Link – learn more here) that is very glossy, quite thick, and most importantly, dries fully on polymer clay.

I sprayed U-POL on my usual test tiles of Sculpey III, Premo, Kato Polyclay, Souffle, and Fimo Professional as a first test. All tiles dried within five minutes. I gave the tiles a second coat, which also dried right away. The finish was thick, glossy, and smooth. Over the next two months, I checked the tiles regularly and there has been no degradation or stickiness. In addition, the spray is VERY DURABLE. I cannot scratch it off with my fingernail, unlike all the other sprays I’ve tested. The finish also seems to be quite flexible. It doesn’t crack when you flex the tiles (this feature is important because polymer clay is flexible).

There is a wee bit of curling, which is typical with many thicker coatings (such as resin) and won’t be a problem on thicker pieces of polymer clay. But you can see the slight upward curl on these thin tiles.

Using U-POL on Polymer Clay

I’ve now used this spray on several projects and I’m thrilled with how well it performs. Unlike the spray paints that I’ve used for other crafts, this stuff can be sprayed on quite thick. It didn’t get goopy when I sprayed it on as a solid, glossy sheet. (Light sprays will be spotty and uneven.) It still dried right away.

The above samples (which are Cernit Metallic using the mica shift technique) were half-covered with masking tape, then sprayed with two coats of U-POL. After 30 minutes, the tape was removed. It didn’t pull or peel. It was remarkably clean. You can see how much the spray changed the gloss of the surface.

I did have one partially bad result. I coated some beads with chameleon nail powders, baked them, then sprayed them with U-POL. The finish turned milky and dull.

But the cloudiness disappeared when I put the beads into at low oven (about 200F for 15 minutes). You can see these beads below. I’m still not sure why those beads had that issue. I’ve not experienced this with other materials and not with plain polymer clay.

The finish that U-POL leaves is thicker and more plastic feeling than Varathane. But for some things, like these beads, it’s the perfect finish.

While the spray did leave an odor on the beads for a while, it disappeared after a couple of weeks and now I can’t smell it on the pieces. BUT that doesn’t mean it’s not toxic to breathe. You MUST MUST MUST spray this outdoors. No, not in the hallway or the garage. Go outside!

What I Don’t Know

I’ve only been testing U-POL for just over two months thus far. In my experience, that’s enough to test for stickiness. It does not seem to be having an adverse chemical reaction to the polymer clay. And I’m only one person, too. Some things won’t be obvious until a lot of people use this spray and compare notes on how well it’s working as a spray varnish for polymer clay. So don’t use it on anything important until we know more, okay? But if you’re ready to give it a try, I think it’s time to spread the word!

I don’t yet know how well this spray will hold up over time. I don’t know if it will turn yellow or become brittle. Those are not features of this spray, generally, as it’s used on cars and in full sun. But time will tell and I’ll update this article as time goes forward.

Where to Buy U-POL

If you’re in the US, you can buy U-POL on Amazon (Affiliate Link – learn more here). Those of you in the UK can find it at Halford’s and also on Amazon UK (but it’s not showing for me). Canadians will find that here’s a source. In Australia, it’s on Amazon as well as several other sites.

The best way to find a source is to do a search in your own area. Due to the regionalization of search and websites, it’s nearly impossible for me to see what you see!

What About the Other Glossy Sprays?

I’ve not been able to test these, but they have been put through their paces by experienced clayers. I’m sharing them here with you in case you can’t find U-POL in your area and still need a good glossy spray clearcoat for polymer clay.

Jennifer Summers has shared that in the UK there’s something called Simoniz Clear Acrylic Lacquer that gives a thick, glossy coat and hasn’t had any problems for her.

And Karolina Söderberg has shared that she’s not found U-POL in Sweden, but that she always uses Motip Gloss Spray. In fact, the mushroom beetle house that she made me was coated with Motip Clear Varnish Spray and it’s holding up nicely. Motip Clear Varnish is also available from Amazon in the UK. I suspect it’s available all through the EU, but I’m not sure.

Since all of the above gloss sprays are automotive clearcoats, I wondered if Duplicolor Clear (commonly available at auto parts stores across the US) would also work. Sadly, it was also sticky on all brands of polymer clay. Stick with U-POL if you can find it!

Is U-POL a Substitute for Resin?

While UV and epoxy resins make a thick, perfectly shiny coating on polymer clay, they’re messy and present health hazards. Many people are looking for a substitute for resin for making polymer clay earrings and other jewelry. Will U-POL work for this? Sort of.

You see, glossy sprays are not thick enough to make a self-leveling coating the way that resin does. They’ll conform to the surface as they dry, accentuating any flaws by making all the fingerprints and marks shiny! So yes, U-POL can work as an alternative to resin, but you need to sand the surface perfectly smooth first. And if you’re going to go that far, I’d just give the pieces a quick buff. A sanded and buffed finish is superior in smoothness to a sprayed gloss coat on polymer clay. But for beads or something that you can’t sand and buff? U-POL is a fantastic choice!

Try U-POL!

If you’re so inclined and are in need of a glossy spray varnish for polymer clay, give U-POL a try (Affiliate Link – learn more here). If you do, please comment with your experiences so we can compare notes. I’m really curious if this turns out to be as good as I hope it will be. Let me know in the comments below! Also, if you’re in other countries that I’ve not mentioned, and you’ve found U-POL where you live, please share the link in the comments to save others the trouble. Thank you!

By the way, members of Blue Bottle Insiders knew about U-POL at the beginning of my tests, we’ve discussed this topic in several of our Studio Drop-In Sessions. The Insiders get to join me in my studio and get extra insight about what I’m working on. Join us!