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Front Cover image from FreeForm Peyote Beading: Design and Creation of Original Wearable Art Jewelry

Freeform Peyote Beading: Design and Creation of Original Art Jewelry

Published September 2010
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Setting up the workspace - design & pour concrete cabochons

Concrete Cabochons Part One: Design, Mix and Pour

Mixed-media artist Robert Dancik first introduced me to the wonders of using concrete to make unique cabochons (he called them 'billets') back in the spring of 2008 at the Penland School of Craft.

Since then, I've continued to explore the possibilities, and have used several concrete cabs in my bead work.

Plastic utensils for mixing, shaping concrete

From left: Teaspoon Measure, three palette knives various shapes, plastic dinner knife, plastic spoon

Concrete Tinted with Procion Dyes

Tinting Concrete with Procion MX Dye

While I could buy dyes and stains made specifially for concrete, they are generally sold in large quantities which make them pricey.

I almost always already have procion dyes around my studio. Left-over dye mix no longer suited for dyeing fabric is still quite useable for painting papers or tinting concrete. The resulting colors will dry to pastel shades of the original dyes.

Once dry, you can add additional layers of color with acrylics or other paints. Finally, a top coat of resin will deepen and enrich the colors, but should be used as the final layer after all other work is complete.

Dye Recipe: 1 Tablespoon dye power to 1 Cup water. Measure dye powder into mixing cup, add 1/4 cup water, stir until dye power is disolved into paste. Add additional water and stir.

My procion dye mixes are extremely concentrated as I use them for several different purposes. While I typically use them full strength in tinting concrete, you may choose to use less dye powder or dilute the dye mix with water.

I work with six dye colors - scarlet, fuschia, turquoise, navy, golden yellow and lemon yellow - and two blacks. Any other colors I need can be mixed from these. When working with concrete you can either premix the dye liquids into an extra cup or mix two slighlty runny batches of concrete and mix the two together.

If you're premixing the dyes, note that darker colors have far greater tinting strength than the lighter colors. To get a mid color green, for instance, t mix 3 teaspoons golden yellow with 1 teaspoon turquoise.

Supplies - Mixing

  • Concrete - a fine aggregate, finishing concrete works best
  • Rubber gloves
  • Small, clear-sided mixing cups (soft-sided plastic lasts longer than hard)
  • Plastic spoons
  • Measuring cup - 1/4 cup
  • Measuring spoons - teaspoon in particular
  • Plastic palette knife(knives)
  • Paper Towels
  • Wide-mouthed jar/container with clean water for rinsing utensils
  • Clean water or dye liquid

Supplies - Design & Layout

  • Blue Painters' Tape 2-3" (found in the paint section of most hardware stores)
  • Glass, shells, stones, beads, coins, wire, plant material, washers, or any other small objects you'd like to try including in your designs
  • Optional
  • Inexpensive craft tape
  • Raw polymer clay for resists/voids/forms
  • Matte medium & to coat porous items before embedding them in concrete
  • Thick-walled rubber bands (like those that come wrapped around brocolli or asparagus)
  • Tray, cookie sheet or other flat work surface
  • Sharpie or similar marker

Design Work

Start by laying out several strips of blue painters' tape a couple of inches apart sticky side up. Use additional painters tape or masking tape to secure the ends of each strip. This will be your design surface.

Outline each cabochon shape on the painters tape with your marker or use a thick-walled rubber band to define the space.

laying out designs and pouring concrete on blue painters tape

Inclusions can be added to the concrete in one of two ways - laid out beforehand on the blue painters' tape then covered with concrete, or placed on top of concrete that has already been poured. There are advantages and disadvantages to both:

Embedded Below: Best with relatively flat objects like coils, washers or the flat sides of beads. The front face of your cabochon will be flat and smooth. However, concrete may seep under your object if they're not firmly adhered to the painters tape, requiring sanding. And thinner objects like sequins may stick to the tape too strongly and peel away from the concrete when you remove it from the tape.

Embedded Above: Best with more dimensional objects or when you want the front face of your cabochon to have a rounded, beveled edge. However, objects may sink into the concrete and it can be difficult to get a level placement.

two samples of concrete with voids - glass with empty space behind and concrete donut

Protecting Voids, Empty Spaces: Sometimes I want to preserve a void in the concrete - such a when I'm working with transparent objects like glass - where I want the concrete to surround the glass, but don't want it behind the glass. Or when I want to create a concrete donut. Use raw polymer clay to fill the areas where you don't want the concrete. Make sure the polymer clay is soft and flexible. Shape it as desired and stick it firmly in place on your design surface or the front or back of the object you plan to protect.

glass sandwiched between two layers of poly clay

Above left: concrete donut (pictured in design photo above: middle row, second from left - note how much darker the concrete appears when wet).

Above right: there is no concrete behind the green glass so background colors and images can be seen through it (also pictured in design photo: middle row, far left)

Left, the sea glass in the center is sandwiched top and bottom between two layers of red polymer clay before the concrete (also red) was poured around it.

Mixing & Pouring Concrete

mixed concrete in plastic cup (dyed red)

Make sure that all of your design work is done before you start mixing the concrete. Once you've added water, you have a very short working time before the concrete begins to set. Once it begins to harden, you cannot add more water to the mix or you will weaken the resulting concrete. Concrete doesn't harden by drying, but due to a chemical reaction that begins when the water is added.

Measure one quarter (1/4) cup concrete into plastic cup.

Add 2 teaspoons of liquid (water or dye liquid) and stir with plastic spoon. At this point, the concrete should form into pea-sized pellets meaning you're almost there.

Add additional fluid 1/2 teaspoon at a time, stirring thoroughly between.

Do NOT make the mix too runny! Ideally, the concrete should be thick enough that it falls of the spoon in thick clumps - if it's too runny, add a little concrete powder.

Rapid Set Cement All concrete sold in a 25lb blue & white box

Ladle concrete onto your designs a half spoonful at a time, using your palette knife to helps shape the concrete as you work.

Each 1/4 cup batch of concrete should make 3-5 cabochons, depending upon their size and thickness. Most of mine are approx 2-3" and between and eighth and a quarter inch thick. That's about as much as I can reliably work before the concrete gets too hard to be workable. The concrete I work with begins to harden within 15 minutes from the first introduction of water.

Note: It's probably not a bad idea to wear a dust mask while mixing concrete or procion dye powders. I almost always wear a mask when mixing dye powders, almost never when mixing concrete, but that's just me.

Clean Up & Curing

As soon as you're done with a batch of concrete, take a moment to clean up your mixing cup and spoon.

Do Not rinse the concrete down your drain (unless you really want to replace your plumbing). Instead, use your palette knife to scrape as much of the concrete out of the cup as possible, then wipe with a paper towel. You can then finish with a quick rinse now that you've removed most of the particulate matter.

The concrete will feel dry to the touch within an hour. If you are very careful, you can begin peeling your pieces off of the tape at that time. A warning however: the concrete will still be fragile and may break if you fiddle with it too early. If it does break - don't dispare, you can still use it either by embedding the pieces into a new layer of concrete or by cementing them together with a layer of resin. Possibilities abound.

Next: Concrete Cabochons Part Two: Sanding & Painting

All contents © Karen Williams unless otherwise noted
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Last Updated: January 18, 2012