11/02/2019

River Table Hacks: 4 Steps for Success

River tables have become immensely popular in the last 2 years. 

river-table Half Baked Art and Dillweeds Custom Wood

There are so many videos, images and tutorials on social media! But, very few with solid information. Here are some simple, but essential, steps to successfully pouring an epoxy resin river table.

TOOLS & MATERIALS    

Extech moisture meter

Moisture meter
Solvent-safe foam roller
Chip brush
Spray bottle
99% Isopropyl alcohol
Clean, lint-free cloth
Heat gun

DRY 

All wood substrates (surfaces) must be completely dry before adding epoxy resin. Kiln dried wood is best for epoxy application. This will also prevent the wood from absorbing moisture from a humid environment. For naturally dried wood, the moisture level should be 12% or lower.  Use a moisture meter to get an accurate reading. 
Trapped moisture will eventually expand and cause your epoxy to bubble up from underneath. Combined with heat, it will soften and the bond between the wood and resin will fail. The bottom line is never put epoxy resin on wood that has not been properly dried to 12% or below

CLEAN  
spray-bottle-and-clean-lint-free-cloth

For best results, you should apply resin on a squeaky clean surface, free from dust, debris and oils. Oils are deposited on the surface from your skin. (Every time you touch the wood, your fingers leave an oily residue behind). Depending on the type of wood you have chosen to use, the steps to achieving a clean surface will vary. 
If you have chosen a cradled birch wood panel, it should be sanded and "ready-to-use".  All you need to do is spray the entire surface with 91% isopropyl alcohol and wipe clean with a soft, lint-free cloth.
If you are using a live edge slab, you will most likely have a lot of work to do before you are ready to clean. Use a air hose to clear all the dust off of the wood. Using 91% isopropyl alcohol, spray and wipe clean with a lint-free cloth. Repeat until the surface is completely clean. (Denatured alcohol works too)

SEAL   
apply-seal-coat-with-foam-roller-for-epoxy

All epoxy resins should be applied in two coats: a SEAL COAT and a FLOOD COAT.  Applying a thin coat of epoxy, with a solvent-safe foam roller or chip brush, to the entire area that will be covered with resin.  Here are four reasons to seal:
  1. Sealing prevents outgassing of air bubbles into the flood coat of epoxy. 
  2. Sealing prevents color bleeding. Thirsty wood will soak up epoxy, changing the appearance of the wood and any color used will "bleed" into the wood. 
  3. Sealing adheres objects or debris into place and prevents contamination of the flood coat.
  4. Sealing will make your mold or form watertight and eliminate any possible leaks when pouring the flood coat.
Although one seal coat may be sufficient, a second seal coat may be needed. You should have a glossy finish across the entire wood surface after your seal coat(s) dries.
Do not worry about air bubbles in the seal coat. Just apply and let dry! Your flood coat will cover imperfections. You do not need to sand between coats, as long as you apply the next coat within 72 hours. I do suggest cleaning the area with alcohol between coats.

FLOOD  
Pouring-epoxy-resin-flood-coat-HalfBakedArt

This is the main layer of epoxy resin for your project. It is applied generously and thoroughly to the entire area at once. This thick layer will "self-level" and produce the perfect glass-like finish of epoxy resin. Always read and follow the manufacturer's directions, as every kind of epoxy resin is different in several ways.
Depending on the type of application, more than one flood coat may be required. Some casting epoxies are limited to an inch deep, while others should not be poured less than 2 inches deep.

FINISH COAT

An optional clear top coat of epoxy is recommended when you want the professional finish. A clear coat adds depth and dimension while it amplifies the contrast of colors in the flood coat. This top coat should be a standard epoxy (not casting) which is more viscous, self-levels to 1/8 inch, cures faster and to a harder, more durable finish. This same resin makes for a better seal coat as well.  This coat should be poured on and allowed to self-level. If it is necessary to "spread" this coat, use a notched trowel spreader to assure the right thickness. 

AVOIDING & REMOVING AIR BUBBLES  
using-heat-gun-to-remove-air-bubbles-from-epoxy-HalfBakedArt

Air bubbles are normal, in small amounts, and often present in liquid epoxy resin after mixing the correct amount of Part A & Part B.  Let's look at what causes air bubbles- Temperature, moisture, excessive whipping, outgassing from the substrate, surface and/or embedded objects- all of which are avoidable.
  • Epoxy (Part A and Part B) should be acclimated to room temperature before using, as well as your wood. Room temperature should be 70 -78°F. (74° ideal). 
  • Water is kryptonite to liquid epoxy resin! It will ruin your epoxy mixture and project. A dehumidifier is a great idea. Moisture contamination can come from unexpected sources. ex: Humidity level, sweat, condensation from air conditioner, damp wood, wet paint, adding water-based pigment (food coloring, water color, tempura paint, etc...) utensils, buckets, mixing cups or anything with a drop of water
  • When mixing, hand mixing is best. Keep your mixing stick on
    mixing epoxy-resin-by-hand-HalfBakedArt
    the bottom of the cup to prevent whipping air into the mixture and scrape the sides, bottom and stick repeatedly during the mixing process. If you do have some bubbles after mixing, let the bucket/cup sit for 30 seconds and use a heat gun to zap the layer of bubbles off the top before pouring. Also, add the epoxy mixture one third at a time using a heat gun to remove bubbles from each layer
  • For general de-gassing, I strongly recommend a heat gun, held 4-6 inches above the epoxy resin, continuously moving in a sweeping motion across the whole area. You can repeat this after 30 minutes if needed. 
  • Outgassing was covered in the seal coat section. This applies to any and all objects that will be covered with resin. (rocks, pebbles, shells, coins, photos, dried flowers, etc...

Choosing a low viscosity epoxy is essential for the flood coat. If you follow the steps outlined here, you won't have a problem with air bubbles. Try using a high viscosity epoxy for sealing and/or top coating for better coverage and faster curing.



Ruler measures inches and centimeters


CHOOSING THE RIGHT EPOXY

Every brand manufactures multiple resins, each is made for a specific application. In addition, there are many types of resin, again, each one designed for a different use. Be sure you select an epoxy resin made for your type of project. The wrong epoxy will not work! I recommend FlowCast by EcoPoxy.

If you are making a river table (pouring a layer 1/2 inch or deeper) you MUST use a casting resin. These are made to pour deeper than 1/4 inch and are strongly suggested. (recommended depth will vary greatly, read the directions). Deep casting resins are formulated for a slow exothermic process. This is essential to prevent the epoxy from overheating during its exothermic process. On the contrary, epoxy resin must reach the peak exotherm temperature to cure to its full strength. Therefore, using fans to "cool" curing resin is a bad idea. 

There are several brands of casting epoxies available. Each is designed for different uses/applications.  Casting jewelry, turning blanks and pouring river tables are very different applications! Also, it's important to take into consideration the total volume (mass) you will pour. Exceeding recommended volumes is very risky.

Regardless which epoxy resin you decide to buy, please read ALL manufacturers directions before using. Know the minimum and maximum depth that can be poured, as well as, total volume. 

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The Secret to Epoxy Resin Success

The Secret to Epoxy Resin Success: part 1
Preparing for a Resin Pour



The secret to creating great resin art is PREPARATION! Working with epoxy resin is not as easy as it looks. It is not hard, or difficult to learn, unless you are unprepared! Professional resin artists know that this


Epoxy resin: Part A and Part B



Once combined, the clock starts ticking. Literally! You have a short amount of time (pot time) to mix, apply the liquid resin, and de-gas, before it becomes to thick to work with. There are other rules too, so setting yourself up for success is essential to making beautiful resin art and executing an effective epoxy resin pour.



Here are some checklists to guide you through setting up a successful work area.


CHOOSING A WORK SPACE:




  • Large indoor work area (studio, basement or spare room)

  • Optimal temperature and humidity (temperature controlled)

  • Clean and free from dust and debris

  • Sufficent lighting (natural and artificial)

  • Electrical outlets and drop cords (for heat gun)

  • Flat surface for your artwork (table, sawhorses)

  • Additional area for mixing (side table)

  • Trashcan(s)


Optional:




  • running water

  • space heater

  • air cleaner

  • exhaust fan

  • dehumidifier

  • tape measure

  • stool

  • journal and pen

  • storage space

  • shelving





SUPPLIES & MATERIALS:






  • Plastic dropcloths or plastic sheeting to cover all surfaces

  • Apron, smock or painting clothes

  • Hat or hair band

  • Paper towels (lots)

  • Disposable gloves (vinyl or nitrile)

  • Painter's tape (Frog or Blue) wide enough to protect the edge

  • Level

  • Plastic cups (several sizes and lots)

  • Plastic measuring and mixing container (16 oz, 32 oz or larger)

  • Craft sticks or Paint mixers for large pours

  • Rubber spatulas, plastic spreaders or disposable brushes

  • Exact-O knife, tweezers or toothpicks (to remove debris)

  • Implements or utensils for texture or effects (comb, notched trowel

  • Spray bottles

  • Colors (paints, inks, pigments, powders, dyes, tints)

  • Additives and applicators (oils and eye droppers)

  • 91% isopropel alcohol, (denatured alcohol or acetone*)

  • Epoxy resin (EcoPoxy or brand made for artist)

  • Your project or artwork




**If you can't close off the work area during the curing process then use a large cardboard box to cover your artwork. (longer, wider and taller than your project)




Pick A Substrate (surface)




Wood, canvas, tile, paper, metal, acrylic, and so many more possibilities. Epoxy resin can be applied to dozens of surfaces or materials. Get creative with your selection! If you're a resin artist (or epoxy resin painter), like I am, consider using wood panels instead of stretched canvas. If you are coating a stretched canvas with epoxy resin, use rigid cardboard as support to


prevent the canvas from sagging and making the resin pool in the center. *I have also used smaller stretched canvases that fit perfectly under my large canvas project.

*example: (2) 16 x 20" canvases fit under a 24 x 48






PREPPING:


After you have chosen your substrate, there's a little more preparation before you pour your epoxy resin.

TAPE: Tape the back of your artwork with painter's tape to protect it from drips.

CLEAN: Make sure it is completely clean and dry. I suggest you spray the surface with alcohol and wipe clean to make sure it is completely dust-free each and every time you are about to pour.

SEAL: Seal your project, and/or any objects to be coated, with a light coat of resin or a spray-on or brush-on sealant. Epoxy resin is the best choice, using a paint brush (correct size, disposable) foam roller, or spreader, apply a thin quick coat to seal in any air, debris or dust that will definitely contaminate the second coat (flood coat) of resin. This step is so important if you are going to have a perfect finish!

PRIME: If you are going to make a resin art painting, it's a good idea to prime your surface with a thick coat of white paint. Although it is optional, a white surface will show truer, brighter colors. If you are going to leave any negative space, this will provide a smooth background.

**note:I always prime my wood panels with a coat of white house paint, the all-in-one kind, before I seal it with epoxy resin. This gives me a perfect surface to create my artwork and makes the finished painting flawless.









Stress Free Epoxy