barrel firing - paul wandless

The smells and sounds of a crackling campfireare among my fondest childhood memories.My father taught my brother Dan and me howto gather and split wood, and start and main-

tain campfires. This may explain why barrel firing isone of my favorite methods of finishing work. For manyartists, the process and experience of outdoor firing isjust as fun and exciting as the results achieved.

Barrel-fired work produces beautiful black and graysmoke patterns, and blushes of maroon, pink, earthyorange and yellow ochre from different chemical col-orants introduced. Firing in a barrel is simple, but get-ting results you like can be elusive at times. Here arefour basic tips I’ve developed over the years:• Prepare the work properly to take maximum advan-

tage of the heat, smoke and fumes• Use the right combustibles and chemicals for col-

orants when packing the barrel• Have enough hot embers to burn all the combustibles • Leave work in the barrel the proper length of time

Another important factor is to have realistic expecta-

24 PotteryMaking Illustrated • July/August 2006

Successful Barrel FiringBy Paul Wandless

tions of the achievable results. Every firing process hascertain parameters of what can be achieved. Many ofthe colors are subtle and it may take more than one fir-ing to get the desired effects. And, while barrel firingcreates strong contrasts between darks and lights withblushes and flashes of color, you won’t get the cherryreds, true oranges and bright yellows of traditionalglazes and slips. This isn’t to say the colors aren’t lushor rich, only that it’s important to know what’s achiev-able with this process. With enough experimenting andexperience, a wide variety of vibrant colors can beachieved with contrast and intensity.

Green StageThe clay body color and temperature to which you

bisque fire determines whether or not you’re going toget the most out of the conditions and atmosphere inthe barrel. Porcelain, white or light-colored clay bodieswork best to show the more subtle surface colors creat-ed from the smoke and chemical colorants. My claybody is more of a buff color, so I brush a thin coat ofwhite slip (80% EPK and 20% Ferro Frit 3124) onto

Where Burned Up Meets Burned Out

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July/August 2006 • PotteryMaking Illustrated 25

leather-hard work to ensure a light surface for the firing(figure 1). After bisque firing, I use white or light-col-ored AMACO Velvet Underglazes because of their fineparticle size and the broad palette of colors. Use darkerclay bodies and surfaces if you prefer deeper values andricher blacks. Another option is to burnish your workwhile still green. You can apply terra sigillata beforeburnishing or simply polish the clay surface itself.

Bisque StageSince this is a low-temperature, atmospheric firing, a

soft bisque (Cone 010 to 06) is best to keep the claybody porous enough for smoke and fumes to penetratethe surface. This one step alone can dramatically changethe results possible during firing. Bisque your clay bodyat a few different temperatures (for example, Cones010, 08, 06) and see which works best with your clayfor the results you want. After bisque firing, there arestill more decorative techniques to experiment with tocreate interesting effects. My favorite is to wrap copperwire around the work, which leaves deep maroon toblack lines where it touches the surface (figure 2). Thewire gets brittle and breaks off after the firing. Anotheroption is to apply a salt wash or ferric chloride to thebisqued piece. A salt wash introduces sodium, whichaids in developing some yellow and ochre blushes. Soakcheesecloth in a salt solution and wrap it around thepiece or brush salt onto the bisque in select areas.Applying a 50/50 solution of water and ferric chlorideproduces light orange to rust colors. I use a siphonblower to apply ferric chloride (figure 3).

You can also barrel fire a piece of low-fire glazed work(figure 4) for some interesting results. Get a fake rakueffect where smoke is forced into the cracks of a gloss orcrackle glaze, or change the color of the glaze with fum-ing and direct contact with the colorants in the barrel. Toget consistent results, do several tests and keep goodnotes on the glazes and chemicals you used.

Firing ToolsFor a barrel, you can use a full-sized 55-gallon metal

drum, a smaller metal can or even a drum cut in half. Itall depends on the amount and size of work being fired.If using a full-sized drum, drill or punch ¹⁄₄ inch diame-ter holes around the bottom, middle and top about afoot apart to increase the amount of oxygen and keepthe embers burning (figure 5). Avoid chrome trashcansand thin-walled containers. The intense heat melts thechrome or paint off the sides, releasing pungent andsometimes dangerous fumes, and the thin walls get brit-tle over time.

Arrange all combustibles and colorants within easyreach (figure 6). For colorants, use red iron oxide, cop-per carbonate, Miracle Gro (copper sulphate) and/orcoarse salt (figure 7). Combustibles include wood (kin-dling, branches, scrap wood) sawdust, straw and news-paper. Warning: Do not burn any pressure-treated lum-ber or sawdust. Fumes are toxic.

For best effects, begin with a white body or brush white slip ontoa tinted body.

Piece with white slip and wrapped with copper wire.

WARNINGBE EXTREMELY CAREFUL NOT TO INHALE FERRIC

CHLORIDE OR ALLOW ANY CONTACT WITH LIPS. WEARRUBBER OR LATEX GLOVES AND APPLY IT OUTDOORS ORIN A SPRAY BOOTH. FERRIC CHLORIDE IS A CORROSIVECHEMICAL USED AS A COPPER ETCHANT AND SHOULD

BE HANDLED WITH PROPER CARE.

The author carefully spraying ferric chloride on pot (see warning).

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PackingThere are several ways to approach barrel firing and

each has interesting results. You can use more sawdustfor heavier smoke or more straw for a faster firing withless smoke—I’m somewhere in the middle. Use the fol-lowing recommended approach, then experiment withdifferent combinations of materials. You’ll find each fir-ing varies depending on the work, combustibles, col-orants, weather conditions, heat achieved and length offiring. Trial and error is the best teacher, so keep goodnotes on the variables for each firing.

Start with an empty container and make a 2- or 3-inchsawdust bed in the bottom mixed with a little straw.Next, generously sprinkle colorants on top of the sawdustbed then place your work on top (figure 8). Colorantsbeneath the work help to develop color on the undersidefrom the direct contact, and will also fume up the sides.

Pack the barrel in layers keeping in mind that asembers burn, your pieces may fall and shift. Be sure tospace out the work a little to avoid unwanted contactfrom the shifting during firing. After all work is in place,put more sawdust, straw, and small twigs or kindling inand around the work (figure 9). Don’t pack the com-bustible materials too densely. It’s good to have airpockets to help keep the embers burning. A tightlypacked barrel burns slower, smokes heavier and maychoke out after a few hours and need to be relit. A loos-er pack burns a little faster and achieves a wider varietyof colors. I like the faster burning barrel and the moresubtle effects mixed with heavy smoke at the end fromthe smoldering sawdust bed.

After completely covering the work with com-bustibles, sprinkle more colorants on top (figure 10).

Covered jar with Cone 05 crackle glazefired over white slip. This jar is seen in figure 8, and finished on page 24.

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Various colorants (L-R) red iron oxide, Miracle Gro, copper carbonate, salt.

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SOURCES OF COLOR

Copper carbonate, copperwire, Miracle Gro

(Contains copper sulphate)

Flashings of deep red tomaroon and shades of pink

Salt or salt wash, bakingsoda and seaweed

Introduces sodium and givesflashes of yellow and ochre

Red iron oxide and ferric chloride

Flashes of earthtonesfrom peach to rust

Use a 55-gallon drum or a heavy, metaltrash can with lid. Make ¹⁄₄-inch holes 1 foot apart to aid combustion.

Combustible examples: straw, sawdust,newspaper, wood. (Do not use any pressure-treated materials).


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This gives the embers another layer of colorants to burn,and heat to create fumes that affect the tops of theworks and fall down the sides as well. Add another inchof sawdust to complete the layering (figure 11).

This completes one level of packing and I normallyfire only this amount. Sometimes, if I have alot of work,I repeat the layering process and make another level ofcombustibles and colorants. I can usually make threelevels in a 55-gallon drum, and stop layering com-bustibles about a foot below the rim of the container,filling that space with crumpled newspaper and smalland large pieces of wood (figure 12).Firing

Light the newspaper and let it burn away (figure 13).For safety, the fire must be contained inside the can, sodon’t stack any wood above the rim. As the woodburns, continue to add more so the fire stays strong for

about 20 to 30 minutes. This ensures reaching maxi-mum heat and creating a good bed of embers to burnthrough all the combustibles. It will take about an hourfor the fire to burn down to a bed of white-hot embersthat will smolder and make their way to the bottom.Use a metal rod to prod the embers to be sure the fire below the surface hasn’t stalled out (figure 14) since it is not uncommon to have to relight the fire if itgoes out.

It takes about 5–7 hours to burn to the bottom of abarrel with one level of combustible. By the end of thefiring, only ashes and work should remain—a sign of agood firing. Don’t be surprised if some of the workcracked or broke from thermal shock. This is commonwith all alternative firing processes due to the quicknessof heating and cooling.

Sawdust bed with colorants added andwork in place.

8 9 10

Add a final layer of combustibles includingan inch of sawdust.

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First layer of combustibles added includesstraw and wood.

Sawdust added along with more colorantsand other combustibles.

Set a fire with crumpled newspapers anddry wood.

Allow the fire to burn and keep it stokedfor 20–30 minutes.


If you have to leave the barrel unattended, it must becovered so sparks don’t fly. Even if the flames have dieddown, a strong breeze could breathe new life into thefire. I use softbrick as spacers and as a weight for the lid(figure 15). This setup allows air to get in the barrel soyou don’t smother the embers and is the same setupused to smolder the barrel overnight.

Finishing and Cleaning upWhen the barrel has cooled, remove the work and

wash it off with water and a soft cloth. For hard-to-remove ash and residue, use a soft nylon brush. Stayaway from abrasive or metal brushes that could scrapethe work. If you end up with a piece that didn’t take thesmoke and color well, fire it again in the next barrel. Forsafety, always douse the container with water to assureall embers are extinguished.

The surface is typically a dry, matt finish if the workwasn’t burnished, but it can be polished. Paste wax will

Carefully agitate the embers with a metal rod. This loosenspacked materials and encourages complete combustion.

14If you need to leave the can during the firing, secure a lid to pre-vent sparks from escaping.

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Four barrel-fired heads: (L-R), head sprayed with ferric chloride;head with white slip and copper wire; head with white under-glaze and copper wire; head with deep yellow underglaze andferric chloride. All heads were polished with paste wax.

You can add a patina to barrel-fired work by cleaning and polish-ing the pieces with wax. For supplies, you’ll need latex gloves,paste wax, sponge, nylon brush and a soft cloth.

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deepen many of the subtle colors. Apply a thin coat andlet dry 3–5 minutes before polishing with a soft cloth(figure 16). I also use the soft nylon brush to polish thesurface and get the wax out of any crevices.

There’s no one way to barrel fire and get perfectresults, but these barrel basics will ensure a level of suc-cess each firing. Experiment with other combustiblematerials and colorants and see the variety of finishesthat can be achieved. Good luck and enjoy the fire. •

Paul Wandless is a studio artist, workshop presenter, edu-cator and author. His new book Image Transfer and Clayby Lark Books will be released October 2006 and he alsoco-authored Alternative Kilns and Firing Techniques:Raku, Saggar, Pit & Barrel with James Watkins released in2004. For comments or more information, go to his web-site www.studio3artcompany.com.



PotteryMaking Illustrated • September/October 2006 19

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Block or relief printing is a great transfer tech-nique for any kind of image, text or design you want on your work. Whether simple or complex, fi nished linocuts can even be the

fi nished works on their own (fi gure 1). When inked with underglaze or slips, you can use the blocks to print directly onto clay or push them into the surface for embossing. Linoleum or lino, as it’s commonly called, is fl exible and works on fl at and curved surfaces making it versatile to use. Clay, plaster, wood and rub-ber can also be used for block printing.

Creating Your LinocutLino has a smooth gray or brown surface with a back-ing made of a coarse fabric called hessian that helps re-duce cracking. Using a fi ne grit sand paper, remove any oils, scratches or imperfections on the surface before carving. This also makes for a more receptive surface to ink up with underglaze or slip. You can soften the surface of old or stiff sheets of lino by lightly ironing the surface or by holding a blow dryer or heat gun 6–12 inches from the back. Move the heat source in a circu-lar pattern or from side to side and don’t sit still on one area too long. You only need to do this for a few min-utes and the lino will be soft as butter for carving.

Printing and embossing on clay with linocuts

By Paul Andrew Wandless

Assorted linocuts.

Pencil drawing on lino.

Block printing reverses the image so you’ll need to carve your designs backwards so they will print cor-rectly on the clay. You can use tracing paper or carbon paper to reverse the original image onto your block be-fore carving (fi gure 2). This is especially important if using text or numbers.

Carve on a tabletop and use a bench hook or C-clamp to hold your lino in place. A bench hook can be picked up wherever you buy your carving tools for the lino. Traditional or standard lino/wood gouges (fi gure 3) are

Gouges, lino block, bench hook and sandpaper.

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used for carving the surface and can be found in any craft or art store. Never carve with your hand in the path of the gouge and never hold the block on your lap when carving. Gouges are extremely sharp so be very careful when using them.

Once the reversed image is drawn onto the lino, carve away all the areas you don’t want to print with color. The remaining raised areas create the relief image that you’ll print or emboss on the clay. Often I use an image where the orientation is important (fi gure 4).

Printing & Embossing To print the linocut you’ll need a clean, smooth surface, a brayer (small hand roller) and an underglaze or slip that is thick and sticky (fi gure 5). Having the proper consistency to this ceramic ink is key to the success of the image being transferred cleanly. Commercial under-glaze is usually too thin right out of the container, so pour what you need into a small plastic container and let it sit out overnight. Once it’s the thickness of yogurt,

add clear acrylic printing medium to give it the body and stickiness needed for printing (fi gure 6). Shoot for a consistency of honey for the best printing results. An easy option is to purchase a semimoist commercial un-derglaze that’s ready to use right out of the tube and formulated specifi cally for printing purposes.

I use AMACO semimoist underglaze in the ¹⁄₄-ounce tubes for small blocks or single prints, but for larger blocks or multiple prints I thicken the AMACO Vel-vet, GDC or LUG colors in whatever custom amounts I need. With some practice, though, the underglazes can be applied without being thickened or adding any printing medium. Artist Kathy King prints her linocuts on clay using AMACO LUG Black right out of the bot-tle with great success and good image clarity. Once you develop a touch for working with a thinner consistency it’s just as effective as using the semimoist colors.

Before printing, make sure everything is laid out and ready to go. Prepare extra slabs so you can do all your printing at once and not have to stop and roll out more

Half-carved lino on bench hook.

Back: semimoist underglazes, GDC Velvet underglaze, acrylic transparent base printing medium, small container and mixing spoon. Front: clay slab, linocut with baren above it, rubber roller on sheet of Plexiglas.

Stirring the acrylic transparent base printing medium and underglaze to produce a ceramic ink of the proper consistency.

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PotteryMaking Illustrated • September/October 2006 21

Mixing color to make sure consistency is even. Rolling color onto the roller.

Rolling color on the linocut making sure all areas are covered with color.

Colored lino with a little shine (indicates the ink is wet and will transfer well).

Placing inked-up block face down. Rubbing the block with your hands or a baren.

if you’re unhappy with some prints you’re getting. For good printing results, the surface of the clay slabs can be somewhat damp, but not sticky or even in the early stages of leather hard.

Put enough ceramic ink for one print on the Plexiglas and mix it with a stick or a spoon to ensure it’s even

(fi gure 7). Move the roller back and forth over the color until you have an even coat on the roller (fi gure 8). Ap-ply an even coat on the linocut making sure all areas are covered with color (fi gure 9). The ceramic ink should appear wet on the surface of the block when properly covered (fi gure 10).

7 8

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11 12

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piece that’s already built but still in the green stage. This is where your own creativity comes into play based on your work and how best to incorporate the lino image. Thoroughly clean all tools used for the printing process with water.

You may not be a printmaker when you start this process, but you will be an offi cial “Clay Printer” once you’ve block printed on clay. You just need a curiosity of material and an image you want to repeat.

Revealing the print.

Top left: Linocut. Top right: In this print, there was uneven pressure and the ceramic ink was too dry when printed. Bottom left: Shows results of good pressure and color. Bottom right: Shows results of bad pressure on edges; also, ceramic ink was still not wet enough when printed.

A linocut can also be used as if it were a large stamp to emboss a soft clay surface (see photo below). Many artists make custom relief tiles in this fashion. The areas that would normally re-ceive the ceramic ink are now embossed into the clay. Place your linocut face down on a soft piece of clay and rub the back in a circular motion. Don’t press so hard that the lino gets stuck. Peel back and the embossing is complete.

You can also add color in the embossed image to make the design appear as a color inlay. Bisque fi re the embossing, then apply glaze, underglaze, or stain in the embossed areas with a brush or other applicator and let it dry. Use a damp cloth or sponge to wipe the color off the high areas leaving color only the embossed area.

What a Relief

Turn the block face down onto the clay slab (fi gure 11) and gently rub the back of it in a circular motion with your hand or a baren (fi gure 12) to help transfer the color. Don’t wait too long to print the block after it’s been inked or the color will start to dry and won’t transfer as cleanly. Peel the block off slowly from the clay and see how it came out (fi gure 13).

The fi rst print will help you answer three questions. Was the ceramic ink mixed to the right consistency, was enough ceramic ink used on the block for good color results and was there enough pressure used for a clean transfer. Many times this fi rst print isn’t usable and is considered a test print for this important information (fi gure 14). Make the necessary adjustments after see-ing the test print, if any, and then continue printing the rest of your slabs.

After the PrintOnce printed, the clay slabs can be used for whatever handbuilding purposes you want or can even be the fi nished piece if you like. You can also print on a clay

Paul Andrew Wandless is a studio artist, workshop pre-senter, educator and author. His new book, Image Trans-fer and Clay, will be published in October by Lark Books. He can be e-mailed at [email protected] or see www.studio3artcompany.com.

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barrel firing - paul wandless

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