How to Seal Vinyl on Tumblers

Tumblers look a bit boring when plain, whether as presents or for personal use. Sprucing them with adhesive vinyl stickers makes them appear more artistic and visually appealing and adds a personal touch. Read the tumbler heat press guide before DIY vinyl on tumblers.

But what happens when the sticker starts peeling off? Sticking the vinyl on the tumbler is only the first step towards decorating it; it needs protection against jarring elements like water exposure when washed regularly or sun heat. Although custom vinyl stickers are naturally water resistant, using the best sealant for vinyl on a tumbler enhances its lifespan.

Each sealing method prevents peeling in its unique ways:

Tumblers can be used widely, exposing them to both extremes of temperature. You should, therefore, be very deliberate about the sealant you use on it. These are the most common methods to consider. Pick one that is most convenient for your tumbler.

It is a non-toxic and adaptable product mostly used as a sealer and glue on finishes. We recommend Mod Podge for tumblers because of its ease of use, and it comes in a wide variety of finishes, such as glitter, matte, and gloss. It also dries up to form a clear layer over the sticker without yellowing over time, saving the vinyl’s quality for a long time. A few more benefits besides its versatility are its inexpensiveness, and it is available in different quantities, from starter packs to big bottles.

However, it has several drawbacks, such as a long curing time of at least 28 days for dishwasher use and limited durability compared to other methods.

Although it is non-toxic and safe on the skin, it might result in irritation on sensitive skin. Working with gloves in a well-ventilated room is recommended. Mod Podge is highly flammable in its liquid form, so proper storage away from the heat is advisable.

Using epoxy resin for tumblers requires a mix of two chemicals, resin and a hardener, to provide a coating. The chemicals are easily accessible in craft stores but might cause a considerable dent in your wallet. Different chemical brands have different viscosities and curing times (an average of 72 hours), but they will self-level on the tumbler to create an even layer. When properly mixed and applied, the result is a smooth, durable, and thick coating. While epoxy has held up its durability reputation well, it is prone to yellowing after a while, ruining the quality of the vinyl.

The application process is complex and tedious, and if not done right, it might result in the formation of bubbles. You have to get your mixing stamina ready as you need to continually stir for about 15 minutes non-stop to achieve the best results. Uncured epoxy releases harmful fumes that might result in health complications when inhaled. Use a respirator mask and PPE, and work in a well-ventilated room to prevent chemical exposure.

This water-based sealer is relatively easy to apply compared to other methods, as it comes in either spray or liquid form that is ready for application. Applying thin layers lets the sealant completely dry off before moving on to another one. If done incorrectly, it might leave brush marks or turn cloudy.

The biggest potential downside when using polyacrylic for tumblers is the limited durability, especially when exposed to water or heat before it completely cures. 

Now that you know the common sealants, you might wonder which one is the best fit for different tumblers. But first, let’s go through the common steps to apply sealants on all tumbler types.

Step 1. Prepare the supplies 

Although the supplies might differ with different sealants, there are common ones you must have before starting the application process. Get your tumbler, the sealant, cleaning supplies, alcohol, a piece of cloth, a brush (if the sealant isn’t in spray form), masking tape, and PPE in a well-ventilated room. The tumbler should already have a properly cured and smooth vinyl design.

Clean and dry the tumbler to remove any dust and oils that might form bubbles on the sealant. Any adhesive remnants on the vinyl's edges should also be wiped off using a clean cloth and rubbed with alcohol.

Step 2. Cover unwanted parts 

Using the tape, cover all the undesired parts to prevent accidental spillages that might ruin the tumbler's final look. Parts of the tumbler that are textured, rough, or made of different materials might react differently to the sealant, resulting in uneven finishes. Covering them up keeps the intended areas clear for sealing.

Step 3. Apply the sealant 

Follow the manufacturer’s instructions to mix and apply the sealant. Unless additional requirements are stated, carefully spray or apply the sealant, spreading it to achieve a smooth and even layer. Aim to apply a thin layer at a time instead of a thick layer at once. Ensure no bubbles are formed inside a layer before allowing it to dry.

Step 4. Dry between coats 

The manufacturer’s instructions state how long it takes for a single layer of the sealant to dry off. Depending on the thickness, it might take a few minutes or hours to dry. Do not be in a rush to move on to the next layer before the previous one is completely dry.

Step 5. Cure the sealant 

After the final layer is dry, it is imperative to cure the sealant for durability and a quality impression. The curing duration depends on the sealant used, with the longest duration being for Mod Podge, 28 days. The average curing time is 72 hours for most sealants. Exposing the tumbler to water or heat before it is completely cured softens the sealant, leaving it vulnerable and might leave a cloudy patch.

Step 6. Clean up 

At this point, you are almost done with sealing and are just waiting for curing to finish so you can use or hand over your tumbler. Clean up the working station and supplies before storing them. Rub off any chemical spillage from surfaces to prevent contamination.

For the best results, you have to use the recommended sealant for different tumblers.

Epoxy resin is recommended for stainless steel tumblers because of its strong bonding capabilities with metallic surfaces for a smooth and flawless finish. The chemicals in the sealant can also withstand wide temperature ranges.

Application process:

Mod Podge is the sealant used on ceramic mugs because it adheres to the porous ceramic surface. It is also water-based and non-toxic, making it safer to use compared to other sealants. Mod Podge is widely accessible and affordable.

Application of Mod Podge on ceramic mugs.

Application process.

Most crafters prefer epoxy resin as the sealant for glass mugs, mostly because of its tough finish. It also bonds strongly with glass, regardless of the thick layers. The transparent nature of the resin retains its glossiness for a considerably long time.

Application process of resin on glass.

Clear acrylic spray is the most preferred method to seal vinyl stickers on acrylic tumblers because of its compatibility with the surface, quick drying time, and cost-effectiveness.

Application process.

Sealants are designed to elongate the life span of the vinyl design, but only with good vinyl tumbler care. To ensure your sealed vinyl’s longevity, here are some tips.

• If possible, handwash your tumbler using mild soap and soft cloth. Dishwashers expose the sealants to heat stress and mechanical agitation that degrades their quality, making them soften or yellow. The harsh chemicals in the detergents might also react with the sealant, damaging it.

• Reapply your sealant . If you didn’t get it right the first time, repeat the process, following the manufacturer’s instructions to the letter to boost your odds of creating a durable and quality seal. Allow for the advised curing time before using the tumbler. Complete curing ensures a smooth surface, a consistent finish, a strong bond between the sticker and the tumbler, and resilience to dust and other contaminants.

• Avoid exposing the tumbler to extreme temperatures in the microwave or the freezer. If you expose the tumbler to hot beverages, use another one for hot ones and keep the consistency. Different temperature ranges affect the adhesive on the vinyl and might degrade the quality.

• Regularly inspect your tumbler for any irregularities like peeling or cracking of the sealant.

Lastly, let’s deal with the common myth in the craft world that vinyl shouldn’t be sealed to allow it to “breathe.” Some people swear that sealing vinyl stickers on tumblers traps air, leaving bubbles that get worse with time. Vinyl is a non-porous synthetic material that doesn’t need breathing. In fact, a proper sealant prevents bubbling and deterioration of the vinyl when exposed to environmental factors.

There is no one-size-fits-all sealant. Your choice depends on your project, availability of products, and preference. Different projects and designs call for different sealers. For example, if you are designing your tumbler to gift someone, you might want to add some fancy glitters to enhance the look, so your go-to sealant would be epoxy.

Now that your question on how to seal vinyl decals on tumblers is answered and you are bound to make quality seals, experiment with different sealants and designs to find one that gratifies you best.