Due to its cured strength, adhesive properties, heat resistance, water resistance, and chemical resistance, epoxy resin has a multitude of uses in marine, residential, industrial, automotive, aerospace, construction, electronics, and other industries.
Marine uses for epoxy include boat building (including canoes and kayaks), boat repair, composite fabrication, laminating, coating, sealing, wet layups, filleting, filling, gluing, and bonding. Non-marine uses for epoxy resin include structural adhesives, glues, paints, primers, protective coatings, floor coatings, wood rot repair compounds, insulators, motors, generators, transformers, epoxy river tables, crystal clear bar tops and countertops, epoxy art, turning blanks, woodworking applications, and more. Aside from its versatility, epoxy is ideal because it bonds to a lot of different materials, including fiberglass, wood, metals, ceramics, glass, and most plastics. It can also be sanded, drilled, machined, primed, and painted, once cured.
Marine epoxy typically refers to marine-grade epoxy systems developed specifically for marine environments where the cured surface may have frequent exposure to water and chemicals, such as fuel and solvents. Two of the most common traditional marine epoxies used in boat building, repair, and restoration, are TotalBoat Traditional 5:1 Epoxy and West System 105 Epoxy. Other marine epoxy products include the 2:1 low-viscosity systems, such as TotalBoat High Performance 2:1 Epoxy and MAS Low Viscosity Epoxy Resin.
Both traditional and high-performance epoxy systems are ideal for high-strength bonding applications, laminating, filling, coating, waterproofing, and structural fiberglassing. These epoxies can also be combined with various fillers to create thickened material for fairing and filleting. In general, traditional 5:1 epoxy has greater strength, but 2:1 is less rigid and cures crystal clear, making it ideal for clear coating a wooden canoe or kayak.
The best resin system for a river table depends on how 'deep' the river is. For river tables that are greater than 1/2" to 1" in depth, clear, deep pour epoxy systems, such as TotalBoat ThickSet Epoxy and MAS Deep Pour Epoxy are ideal because you can pour the epoxy much deeper per single layer than epoxies designed for coating and laminating. Alternatively, clear table top epoxy and high performance 2:1 epoxy systems are ideal for shallow-channel river tables, because their maximum pour depth is 1/8" to 1/4" per single layer. For pouring deeper channels, using these epoxies would require multiple shallow pours, due to the exothermic (heat-producing) reaction.
All of these types of epoxy can be tinted to achieve unique design effects, but the the trade-off with using deep pour resin is that, although you can pour deeper single layers, the epoxy takes longer to cure. It's also important to note that deep pour and super deep pour epoxies have different mix ratios, working times and cure times, so it's important to read all directions carefully.
For a beautiful, durable, epoxy table top like you see in restaurants, choose a crystal clear epoxy system. This will result in a high gloss finish that still looks wet even when it's completely dry. Ideal epoxies for clear table tops include TotalBoat TableTop Epoxy, TotalBoat High Performance 2:1 Epoxy, and West System 105 Epoxy Resin paired with West System 207 Special Clear Hardener. Another advantage of these specific epoxies is that they resist blushing. Amine blush is a waxy substance that can form on the surface of some epoxies when they cure. It can make the cured surface look hazy, gray, cloudy, milky or opaque. While such blush is water soluble, it has to be removed before overcoating with more epoxy or some other type of coating in order to achieve proper adhesion.
It's important to note that non-blushing epoxy systems still have a remote possibility of creating an amine blush under certain conditions that can include moisture or a temperature change while the epoxy is curing. As a precaution, assume blush may be present and wash the cured epoxy surface with clean, warm water and an abrasive pad and allow it to dry completely before overcoating.
This question doesn't have a simple answer because all epoxies are not the same, and the best epoxy resin for wood depends on what you're trying to accomplish. Epoxy has many uses in building and repairing wooden boats, canoes, and kayaks, sealing, waterproofing, clear coating, gluing, bonding, filleting, fairing, fixing rot, and filling cracks and knots. It's also used in woodworking and crafts to create live edge wood slab tables, river tables, tables with embedded objects, clear table and countertops and much more.
For applications where the clarity of the resin is important, a clear, low-viscosity, high-gloss system like TotalBoat High Performance 2:1 Epoxy or MAS 2:1 Epoxy is versatile enough for all of the applications listed above. Alternatively, traditional 5:1 epoxy such as TotalBoat 5:1 is ideal for wooden boat building, restoration and repair projects. However, 5:1 systems do not have the cured flexibility or clarity of 2:1 epoxy systems.
Porous wood should be covered with a very thin seal coat of epoxy because the wood can contain voids, knots, cracks, or holes that trap air, forming ugly bubbles on the surface. It doesn't matter what type of wood you're using -- old reclaimed wood, new bare wood, soft wood, or hard wood -- you should seal it before applying coating or encapsulating flood coats of epoxy. In addition to preventing bubbles, sealing wood forms a stable base for the flood or build coats, and helps ensure maximum adhesion to the wood. In most cases, you can use the same resin for the seal coat as for the flood coats.
Epoxy is ideal for bonding dissimilar materials, and most types of epoxy will stick to many different surfaces, including wood, metal, fiberglass, composite reinforcement fabrics, glass, ceramics, and some plastics. Epoxy will not adhere to plastics such as nylon, Teflon, polypropylene, and polyethylene.
Coverage estimates typically refer to how much epoxy is needed to coat a surface at a certain depth. With this in mind, how many square feet does 1 gallon of epoxy cover? With epoxies that have a maximum pour depth per layer of 1/8" to 1/4", the coverage is approximately 25 square feet @ 1/16" thickness, 12 square feet @ 1/8" thickness, and 6 square feet @ 1/4" thickness. It's important to note that these estimates don't account for epoxy that runs over the edges of the surface being coated, or that is left in the mixing cups. Add an extra 5% for these types of losses.
When measuring two part epoxy components, take care not to add extra hardener. Adding more hardener than specified in the mix ratio will not make the epoxy cure faster - it'll change the chemical composition of the material, resulting in an improper cure - or no cure at all. It's very important to measure the precise ratio of resin to hardener, whether measuring by volume, by weight, or by using metered pumps. If you add too much hardener and end up with a sticky mess, scrape it off and start over.
If you want to speed up the cure, use a fast speed hardener if one is available for the epoxy system you're using. You can also make epoxy cure faster by raising the ambient temperature in your workspace using a space heater or heat lamp.
If your epoxy doesn't harden as expected, there are a number of causes. If too much resin or hardener was used and the mix ratio was off, it will never cure. The same is true if the resin and hardener were measured properly but were not mixed thoroughly. Sticky epoxy must be removed, and you need to clean the surface and start over. In such a situation, do not apply additional epoxy over the sticky mess.
Surface moisture or contamination can also result in an improper cure, so take care to prepare the surface, as directed by the epoxy manufacturer. Finally, if the temperature is too cold in your work area, the mixed resin and hardener might not harden within the specified cure time. In cooler weather, allow extra cure time because cooler temperatures make epoxy cure more slowly. To speed up the cure in cool conditions, use heat lamps and space heaters.
Mixing too aggressively, or for too long, will introduce bubbles into the mixed resin and hardener. This can create the appearance of whipped cream or foam, instead of epoxy that's clear and bubble-free. It's important to mix epoxy components slowly and thoroughly, using the double cup mixing method, which involves mixing both components in one cup for 2-3 minutes, then pouring them into a second cup and stirring for another 2-3 minutes, taking care to scrape the bottom and sides while stirring. It's also important not to mix longer than directed because the mixed epoxy will begin to heat up, due to the exothermic reaction created when resin and hardener components are combined. Pour the mixture onto prepared surfaces or into prepared molds immediately after mixing.
Temperature can affect how easy epoxy is to work with, and how successfully it cures. Cooler temperatures make epoxy components harder to dispense, harder to mix thoroughly, result in much longer cure times, and in a possible reduction in cured physical properties. Before using epoxy in cooler temperatures, make sure the resin and hardener components, the surface, and the air in your work area are warmed to approximately 70-75°F. Maintain this temperature range while using and curing the epoxy, for best results. In cold conditions, if the system you're using has a fast speed hardener, you can use it to help expedite the cure. Another way to help speed the cure rate in cooler temperatures is to use heat lamps or space heaters to raise the temperature.
In warmer temperature conditions, epoxy cures much faster. To help slow down the cure rate and increase your working time, use a slow speed hardener, if one is available for the system you're using. In addition to temperature, you also want to ensure the humidity level is below 85%, because increased humidity and increased moisture can produce amine blush, a cloudy or flat finish, and bubbles.
Cured epoxy is very durable, scratch resistant, and abrasion resistant, making it a preferred finish coating on countertops and table tops. Small scratches are not as visible compared to other finishes, such as varnish or paint, and can be buffed out easily.
Epoxy is compatible with both varnish and polyurethane finishes. For woodworking and boat building applications, coats of epoxy can be used to seal, stabilize, and waterproof the wood surface. Then, to provide the UV protection that epoxy lacks, coats of varnish or polyurethane can be applied on top of the cured epoxy. Before overcoating with such a finish, be sure to remove any amine blush that might be present on the cured surface. This is especially important for 1-part polyurethane finishes and varnishes that may be incompatible with amine-cure epoxy systems. Always test to ensure compatibility.