Fun with Epoxy: From Bar Tops to River Tables

The art of pouring epoxy is very diverse and is only limited by the imagination of the artist. Epoxies can be used as a coating (bar top, table top), filler (knots, holes, cracks), or component (river table, hybrid turning blanks, pure epoxy pours). There are many different kinds of epoxy, each with specific advantages and disadvantages.

Epoxy is similar to paint since it takes about 80% of the time for preparation and 20% to actually do the pour. The three main things that differentiate epoxies are pot time (how long it stays liquid), demold time (how soon it can be removed from a mold), and allowable pour depth. In order to increase pour depth, manufacturers have to slow down the chemical process, and therefore the epoxy will stay liquid longer. All epoxies can take 3-7 days to cure fully. See the chart at the end of the article for a summary of the different options.

Epoxy specifications comparison chart

Another factor is how multiple layers can be applied. Once cured, epoxies can be sanded with 220 grit, cleaned with denatured alcohol, and then a second coat applied. Sanding creates a mechanical bond to the previous layer. The sand marks will not be visible, but when viewed on edge the different layers will be noticeable. Most epoxies have a time frame when the epoxy is hard enough to apply a second layer, but still able to provide a chemical bond to the first layer. Benefits are a faster build-up rate, no sanding, and a reduced visibility of layering. Amazing Clear can be layered between three and four hours after pouring, so a 1.5 inch pour can be finished in 36 hours compared to about 80 hours for a single pour of Ecopoxy or RiverCast.

Regardless of the type of epoxy, sealing any wood surfaces, including knots and voids, is very important. Not only does it provide containment for the final pour, it also reduces the amount of trapped air which will bubble into the epoxy. A thin layer of epoxy painted with a brush works well, but has a longer cure time. Shellac also works well and dries fast, so multiple seal coats can be applied quickly.

All epoxies can be colored with dyes or powders (including metallic, iridescent, and phosphorescent) for an artistic look. For the outdoors or places with direct sunlight, a UV inhibitor (such as Amazing Clear or Ecopoxy UV) is a great idea. The possibilities are almost endless, and with small volume packages available, getting started is quick and inexpensive.