Does Resin Stick to Glass?

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Epoxy resin is a tricky medium to master in art, but it's quite an addicting one. As you venture further into resin art, you'll likely wonder if resin sticks to glass. And if so, how do you apply resin to glass? So, let's answer that question, give you some tips for your first glass and epoxy resin project, and break down the other materials you can (and can't) bond with resin. 

Does Resin Stick to Glass?

Yes, resin typically sticks to glass. Epoxy resin is a two-component system consisting of a resin and a hardener, which hardens through polymerization. It bonds with the glass surface as it hardens, creating a strong, durable, and heat-resistant connection. 

However, there are some important nuances to consider if you're planning to experiment with glass and epoxy resin art:

  • For optimal adhesion, the glass must be clean and free of oils or contaminants.
  • Some types of resins adhere better than others. Epoxy resins generally form the strongest adhesive bond with glass.
  • To form a sticky bond, the resin must be cured for a set amount of time at room temperature between 75 and 85 degrees from direct sunlight. 
  • Use release agents or mold-release sprays on the glass surface if you don't want the resin to stick.

Once the resin cures and sticks to the glass, removing the glass without damaging its surface is complicated. Resin can be challenging to remove from glass without damaging the surface. The adhesive bond between resin and glass may weaken over time, especially with exposure to moisture or temperature fluctuations, but this process can take years.

Another essential thing to note is that, despite being connected, epoxy resin and glass are entirely separate materials, each with its chemical properties. The two will behave differently if exposed to weather elements like extreme temperatures or direct sunlight, causing the glass and/or the resin to crack. 

How to Apply Resin to Glass: Step by Step Instructions

These are our step-by-step guidelines for applying resin on glass.

Cleaning and Preparing the Glass Surface

  1. Remove all dust particles, oils, and smudges from the glass surface with an alcohol-based cleaner, as these are more effective than household cleaning agents.
  2. Dry the glass completely.
  3. If you plan to separate the resin and the glass at some point, you must use release agents to prevent permanent adhesion. This will only apply to some of you if you're making glass and epoxy art. However, suppose you're using a glass mold. In that case, you'll want to use release agents to remove the resin from the mold without cracking it or the glass.

Mixing and Pouring Techniques for Clarity

  1. Prepare the two-component epoxy resin mix and ensure you use the right amount of resin to bond with the glass properly.
  2. Mix the epoxy components thoroughly for a homogenous solution to avoid lumps affecting the final clarity.
  3. Apply a thin resin layer on the cleaned glass surface. This layer is the base for better resin adhesion to glass and acts as a bonding agent for subsequent layers.
  4. Starting from the center, carefully pour the remaining resin to minimize air bubbles and create a clear piece of art.

As a word of warning, flat glass objects are easier to work with than curved ones. So, if this is your first time, we recommend starting with a flat object rather than a curved one.

Curing Times and Environmental Factors

  1. Observe the recommended curing times to ensure a strong bond forms and allow enough time for the initial coat to cure before applying additional layers.
  2. Ideally, the room temperature should remain between 75-85°F (24-30°C). This temperature range aids in properly bonding resin with glass and prevents premature curing or improper hardening.
  3. The room it cures in should maintain a humidity level below 50%, as high humidity can cause sticky surfaces and uneven curing.
  4. Provide ample ventilation for the resin to cure and avoid heat build-up. 

Potential Issues and How to Avoid Them

  1. Work in an environment with consistent temperature and low humidity. Protect from moisture and dust before and during application.
  2. Ensure thorough surface preparation, apply a thin initial coat, allow adequate curing time, and ensure even spreading of resin across the glass surface.
  3. Consider using a release agent when demolding resin from glass to maintain the integrity of the resin piece.

What Other Materials Does Resin Stick To?

Aside from glass, 

  • Wood: Epoxy bonds excellently with wood, which is why it's our favorite medium for our wooden phone cases and live-edge wood art. However, wood movement due to moisture can stress the bond over time.
  • Metal: Epoxy adheres well to properly prepared metal surfaces, making it useful for repairs and creating composite structures. However, thermal expansion differences between metal and epoxy can be a concern in extreme temperatures.
  • Concrete: Epoxy bonds firmly with concrete, making it great for flooring, repairs, and sealing. However, to prevent moisture-related issues, make sure the concrete is fully cured and dry before application.
  • Plastic: Epoxy sticks to most plastics, making it useful for repairs and mold making, but some plastics, like polyethylene, may require special surface preparation or primers for adequate bonding.
  • Fiberglass: Epoxy bonds exceptionally well with fiberglass, which is commonly used in boat repairs and custom fabrication. Proper surface preparation ensures optimal adhesion, especially for boat and water-related repairs.
  • Ceramic: Epoxy can effectively bond broken ceramics, though the repaired area may be visible, and the bond might not withstand high temperatures or frequent use with hot liquids.
  • Stone: Epoxy works well for bonding and sealing stone and is often used in countertop installation and sculpture repair. It may be challenging to match the exact stone color.
  • Fabric: Epoxy can stiffen and bond fabric, which helps create composite materials or waterproofing, though it will change the fabric's flexibility and texture.
  • Paper: Epoxy can be used with paper to create decorative items or seal them. However, it will make the paper transparent and may cause wrinkling if not applied carefully.
  • Painted surfaces: Epoxy generally sticks well to painted surfaces, making it useful for repairs or topcoats, but be sure to test on a small area first, as some paints may react poorly.
  • Carbon fiber: Epoxy is the go-to adhesive for carbon fiber applications. It is widely used in aerospace and high-performance sports equipment. Still, proper layup techniques are necessary for structural integrity, especially when the stakes are high.
  • Foam: Epoxy can bond foam for insulation or sculptural purposes, but some epoxies can melt certain types of foam.

Glass and Epoxy Resin Craft Ideas: What to Make

We're biased, but a river table is one of our favorite use cases for glass and epoxy resin artwork. In this design, you fill the gaps in wooden slabs with resin to create the appearance of a flowing effect. The glass then lays on top of the wood to complete the look. 

We've also tested resin art ideas such as resin-coated glass paintings, decorative glass tableware and glassware, stained glass art, jewelry, coasters, and suncatchers.

Before you begin your next epoxy resin art project, you should know the materials with which resin doesn't bond.

What Doesn't Epoxy Resin Stick To?

  • Leather: While epoxy can bond leather, it's generally not the best choice as it creates a rigid bond that can crack as the leather ages. It may work on faux leathers, however.
  • Rubber: While epoxy can bond to some rubbers, it could be better for flexible applications as the rigid epoxy bond may crack under repeated flexing.
  • Plastics: Epoxy resin can bond to some plastics, but not polyethylene (PE), often used in plastic bags and containers, or polypropylene (PP), commonly used in food containers and outdoor furniture. Both have low surface energy and chemical inertness, making it impossible for epoxy to wet and bond to the surface.
  • Silicone: Silicone has a non-stick property due to its low surface energy and chemical structure, which repels most adhesives, including epoxy.
  • Teflon (PTFE): PTFE is designed to be non-stick and has shallow surface energy. It actively resists bonding with almost all substances, including epoxy.
  • Wax: Wax has a smooth, oily surface that prevents epoxy from penetrating or forming a mechanical bond, and its low melting point can cause adhesion failure.
  • Grease and oil create a barrier between the epoxy and the surface, preventing direct contact and bonding.
  • Wet surfaces: Epoxy needs to displace air to bond, but water prevents this, interfering with the chemical curing process and weakening the bond.
  • Some rubbers: Certain rubbers contain oils or have chemical structures incompatible with epoxy, preventing strong bonds from forming.
  • Contaminated surfaces: Contaminants create a barrier between the epoxy and the actual surface, preventing proper adhesion.
  • Some plasticizers: These additives in flexible plastics can migrate to the surface, creating a bond-inhibiting layer that epoxy can't effectively adhere to.

Frequently Asked Questions

Can I pour epoxy resin directly onto a mirror?

Yes, you can pour epoxy resin directly onto a mirror. It allows you to mix different colors easily and create artistic effects based on your preference.

Is it safe to use a glass mold for epoxy resin?

For safety reasons, using a glass mold for epoxy resin is not recommended. The demolding process can be challenging and potentially harmful if done aggressively. It is better to use a plastic or dedicated resin mold.

Does epoxy resin exhibit more strength than glass?

Although glass is generally more complex, it is significantly weaker than epoxy resin. 

How can I ensure proper adhesion of an epoxy resin on a glass surface?

Mix the epoxy resin thoroughly before applying it to a glass surface to ensure proper adhesion.