Under Glazes 2014

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underglazeusers guide

how to use underto add color and graphic

to your pottery p

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2/21www.ceramicartsdaily.org | Copyright 2014, Ceramic Publications Company | Underglaze Users Guide | 1

Laura Kukkee: Using Underglazes

for Slip Trailing and Appliqu Techniquesby Anderson TurnerThere is no shortage of application techniques using ceramic underglazes. Laura Kukkee creates her decorationwith underglazes on newspaper then transfers it to a freshly rolled clay slab. She builds up layers of differenctcolored slips and underglaze decoration on newsprint to create a very thin slab. Then she cuts the slab into piecesand uses an appliqu technique to apply the decorated pieces to pots. She also demonstrates silk screened andinlaid appliqu.

How to Make Homemade Underglazes

by Holly GoringWhether you want to make your own underglazes or use commercially prepared underglazes, this article willprovide a valuable understanding of what underglazes are made of and how they behave. Regardless of whichway you want to go with underglazes, knowing how they are made will help you know how to use them moreeffectivelyand that means better chances for success in the studio.

9 Artists Using Colorful Underglazesby David GambleWith so many ways to use underglazes, it opens up so many opportunities. Just take a look at the effects JimKemp gets by spraying vivid colors on his teapots or how David Gamble expertly obtains a sketchbook feel withthinned out underglaze washes. Debra Fritts applies layers of underglazes and removes them to achieve herstunning patinas and Rimas VisGardas maximizes the underglazes ability to provide bold illustrations. Theseartists and ve more explore many possibilities you can delve into to add life and vibrancy to your work.

Underglaze as Overglazeby Courtney MurphyDespite what the name implies, Courtney Murphy discovered that underglazes dont just have to go undera glaze. After running extensive tests, she gured out that some of her underglazes worked in an overglazetechnique similar to majolica. In this article she shares her process from beginning to end.

Underglaze Users GuideHow to Use Ceramic Underglazesto Add Color and Graphic Interest in Your Pottery ProjectsUnderglazes are basically clay-based materials with ceramic stains and metallic oxides added to create a full spectrumof color in your work. Theyre the fastest, easiest, and most dependable way for you to add pizzazz to your pottery orsculptures for just an accent or an entire surface treatment. Like many other art materials, underglazes come in a wide

variety of formsliquid, dry, chalks, pens, and pencilsso no matter what your background, a ceramic surface awaitsyour colorful treatment.



by Anderson Turner

Laura KukkeeDemonstrates How to

Use UnderglazesFor Slip Trailing and Silk Screening Appliqu

It is often taught that artists muststrive to be wholly original. Wemust envision something greatand new and then apply it to

our art, thus astounding all who hap-pen by the work weve made. This isa tall order to say the least. Many a

great idea has fallen by the way sidebecause the artist is unsure of how toexecute the desired result. Often, it isthe subtle change in a technique thatcan lead to impressive results. Oneexample of that type of change is inthe work of artist Laura Kukkee.

Laura, a native of Toronto,Canada, did her undergraduatestudies with Bruce Cochrane at TheSheridan School of Crafts and Designin Oakville, Ontario and developed

this technique in the craft studios atHarbour Front Centre in Toronto.Utilizing slips and underglazes in thedecoration of clay has been happen-ing for thousands of years. From theAncient Greeks and Chinese to the17th-century country English potter,

the use of colored slip has been animportant part of the decorative ar-senal of nearly every clay artist.

Laura is currently working withideas surrounding the notion of afragment. This fragment is in theform of an image or a pattern whichis divorced from its original mean-ing. By pulling fragments outsideof their traditional contexts andrestructuring the way in which theyare presented, meanings become

Untitled, 23 in. (58 cm) in diameter, monoprinted (paint, slip trail,silk screen) slips on soft slabs, glazes, and sand then multired.



more elastic. Her results in the re-search are both exciting and new, andthey offer a chance for individualitythat every artist strives for.

Notes on SlipSlip, as dened by Vince Pitelka in hisbook Clay: A Studio Handbook , isclay suspended in water, usually theconsistency of thick cream. It may becolored and used to decorate surfac-es, or may be cast into plaster moldsto create ceramic forms. For her art-work, Laura uses slip the consistencyof a thick cream as well as a slip that issubstantially thinner. Note : Commer-cial underglazes can also be easily sub-stituted for the slips. She uses differ-ent proportions of water and a small

amount of Darvan #7 to get the owof the slip she desires. Its a good ideato test all slips and underglazes beforeusing them on your own work.

Slip Trailed AppliquWhat youll need: ball syringe, news-print, spray bottle, and plaster slab(optional). Laura sets the plaster ontwo pieces of wood to keep slab wellventilated, thus discouraging mold.You will also need the colored slips orunderglazes of your choice.

Wet a piece of newsprint using aspray bottle so that it is damp but notsoaked. Smooth the paper out onto theplaster slab, so you dont get ridgessmoothing helps the paper absorb wa-ter ( gure 1 ).

Slip Trailing Appliqu21 3

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Remember, whatever color you

use rst is going to be the outline ofthe pattern youre making. Yourebuilding color and pattern from thetop layer down with the backgroundcolor applied last, which is the oppo-site direction one normally works.For this demo, Im using black slip,though I have often used other col-ors. Its a good idea to mix and sieveslip thoroughly beforehand to blendall the materials.

Dip the syringe in the slip and ll

it (gure 2 ). To get the bulb owing,try practicing on an extra sheet of pa-per before beginning ( gure 3 ). Sliptrail pattern or image of your choiceonto paper. Pick the paper up by theedges carefully and hold it up to light

so you can see your pattern better

(gure 4 ). Set the paper aside and al-low slip to dry until the sheen goesaway, then start laying color in andaround the pattern ( gure 5 ).

I like to apply bands of color to-gether behind the pattern. Set asidethe paper and let dry until sheen dis-appears ( gure 6 ).

Again, once sheen is gone, coverthe colored slip with a white slipmade of the same ingredients as yourclay body, with roughly 3% Darvan

#7 added to the mixture. Make surethe slip is really owing. Set asideand allow to dry until the sheen goesaway or youre ready to use. I of-ten apply up to four applications ofwhite slip depending on how thick I

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want the slab to be. Usually though,one application is enough ( gure 7 ).

Take the slip-trailed sheet and coverwith paper, then smooth ( gure 8 ).

Flip the slab over, keeping the newsheet of paper in place. Spray the pa-per with water until damp. Flatten thepaper so that water spreads evenly(gure 9 ). Begin peeling the corner ofthe paper, being careful not to rip theclay sheet ( gure 10 ). This will revealthe slip-trailed pattern ( gure 11 ).

Take another piece of paper andplace it over the pattern. Make sureto smooth it out, as this helps remove

RecipesSheridan Studio

Colored SlipCone 6-10Kona F4 Feldspar. . . . . . 24.6 %Pyrophyllite . . . . . . . . . . 8.2Grolleg Kaolin . . . . . . . . 45.8Bentonite . . . . . . . . . . . 5.1Silica . . . . . . . . . . . . . . . 16.3 100.0%

Plus 15% stain of your choice.

Clay BodyCone 6

G200 Feldspar. . . . . . . . . 45 lbWhiting. . . . . . . . . . . . . . 4Ferro Frit 3124 . . . . . . . . 106 Tile Clay. . . . . . . . . . . . 50Kentucky OM4 Ball Clay . 25Bentonite* . . . . . . . . . . . 3EPK Kaolin . . . . . . . . . . . 25Silica . . . . . . . . . . . . . . . . 45

Plus 2 handfuls of Epsom salts* soak bentonite overnight.

moisture ( gure 12 ). Flip the slabover and remove the paper ( gure13). Now youre ready to cut shapesto apply to your pot, based upon

your design ( gure 14 ).Remove excess clay from aroundthe shapes ( gure 15 ). Gently peelup one of your shapes. Brush sliponto the white side of the piece usingthe same white slip. Because of theDarvan #7, there is no need to score(gure 16 ). Gently press the pieceonto the pot or sculpture youvemade. The pot should be soft leatherhard ( gure 17 ).

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Inlaying Slip AppliquBegin this process in exactly the same wayas the slip trailing. Brush the slips in a de-sign covering the paper. In this exampleRahill is using a large pattern and boldcolors. Set the paper aside to dry ( gure 1 ).

Once the gloss is gone, cover the designwith the white slip made from your clay

body with approximately 3% Darvan #7added to the mixture. Set aside ( gure 2 ).

When the sheen has dissappeared fromthe white slip, carve shapes in the slip. Becareful not to cut through the newspaper(gure 3 ).

When you nish the pattern you shouldbe able to see light through the design.

Inlaying Slip Appliqu

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3 4



Cover entire sheet with black slip.Set aside to dry. When the gloss isgone, cover entire piece with white

slip (gure 4 ).Smooth a sheet of newspaper overthe slab, ip it over and carefullyremove the paper from the patternside, and spray with water, if neces-sary, to keep from tearing the slab(gure 5 ).

Place fresh paper over the slab,

smooth, and ip the slab again. Peelthe paper off the back of the slab.The slab can now be cut into shapes

for appliqu ( gure 6 ).Once the excess clay is removedfrom between the shapes, begin togently peel up the cut out patterns(gure 7 ).

Paint white slip onto the whiteside of each piece and gently applythe shape to the pot ( gure 8 ).

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Silk-Screening Slip Appliqu

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Silk Screening AppliquItems you need: squeegee, spatula, metalrib, small pitcher, brushes, a pointed tool,and various colored slips. Prepare paper thesame way as in the previous examples ( g-ure 1 ). Position the silk screen on top of theprepared paper ( gure 2 ). Pour a bead ofblack slip on the screen at one end only ( g-ure 3 ). Squeegee slip across the screen withsteady, even pressure ( gure 4 ). Use a metalrib to remove excess slip from the silk screen(gure 5 ). Carefully remove the paper from

the silk screen to avoid tearing the pattern

(gure 6 ). After the pattern is screened ontothe paper, let it dry until the gloss is gone(gure 7 ). Apply colored slip over the designand allow to dry ( gure 8 ). After the sliploses its sheen, cover the entire sheet withwhite slip and set aside to dry ( gure 9 ). Flipand add fresh newspaper. When this processis completed, begin to cut out the shapes(gure 10 ) Once the excess clay is removed,gently peel up the cut out shapes ( gure 11 ).Paint white slip onto the white side of the

shape and apply it to the pot ( gure 12 ).



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Three completed forms withapplied slip decoration.



Homemade Underglazeby Holly Goring

The truth is, I was a nerdy ceramics undergradu-

ate student. I wanted to learn everything, rightawayand I loved my glaze calc class. No, really,

I did. I took a ridiculous amount of notes and then putthem all in plastic sleeves in a binder. Im sure I testedevery recipe I could nd or invent. After discoveringcommercial underglaze, I was sure I could make that too.

Smooth, silky, perfectly opaque, commercial underglazeis that wonderful substance that coats and colors both gre-enware and bisque ware with ease (Ive even seen it workon mature cone 04 earthenware), and without aws. And,in terms of color, what you see is what comes out of thekiln, no guessing, no hoping. They are dependable as well;covering large areas quickly with smooth and consistentbrush painting. They take light-colored, transparent orclear glaze very well without dissolving into the glaze dur-ing the ring. Finally, commercial underglaze res into a

hard, unscratchable surface without pinholing or aking

from cone 04 all the way to cone 10.

Commercial UnderglazesToday, most commercial underglazes are formulatedusing frits, which reduce shrinkage, allowing them tobe applied to both greenware and bisqueware. Theyare produced using a colloidal process. A colloid is asubstance microscopically dispersed evenly throughoutanother substance (think mayonnaise or hand cream).Underglaze manufacturers use a chemical process thatemploys a high-shear mixing technology to create col-loids. The substance created does not settle and cannotbe separated out by ordinary ltering or centrifuging likethose in a typical suspension. This allows for completeintegration of all raw materials, including the colorant,during the base mixing stage.

Underglaze applied over red earthenware. White slip was applied to half of each test tile before bisque ring. This isnoticeable in the white, orange, and red tiles where the application was thinner. See recipe on next page.



After many rings and many eliminations, this recipecame very close to replicating commercial underglaze:

Pros and ConsThe results were good, very goodsmooth, creamy,good adherence, versatile at all temperatures, a hard sur-face, and an intense color. The substance worked well onboth clay bodies and in all stages, but was best on bisqueware. Brushability was best with the Sta Flo. I found thattoo thick of an application caused aking and pinhol-ing. The lack of sieving and ball milling did the same. Ifmixed to the correct consistency, one coat was sufcientwhile two coats often was too much. The colors became

muted when red to cone 10 but still held up in hardnessand adhesion. Only small batches could be mixed at atime due to the inclusion of the Sta Flo, which is organicand caused mold to grow in the bucket within a fewdays. The mold could be skimmed off but added un-wanted lumps if it wasnt all removed. And of course theamount of commercial stain to produce the rich colorssimilar to commercial underglazes was ultimately veryexpensive. In the end, mixing this homemade underglazewas a lot of work for a product the manufacturers dojust a bit better, faster, and cheaper. However, if I wantcolors that arent available commercially, now I knowhow to make them.

Developing the RecipeVariations of underglaze recipes were available on the In-ternet but not much could be found in textbooks, beyonditerations of slips (clay suspended in water, formulated tot either to wet or dry greenware) and engobes (generallya lower clay content, most often ts greenware and bisqueware ). Few of these recipes encompassed all the charac-teristics I was looking forsomething similar to commer-cial underglaze. Not too much to ask, right?

I started by choosing a clay and a ux. I needed a fairlyheavy clay content for adhesion to the clay body, and anequal amount of ux to lower the melting point of the sili-ca, and to create a hard surface. My clay choices included:EPK kaolin, calcined kaolin, OM-4 ball clay, and talc,all fairly white ring as to not add to the color, and eachcontributing something different to the adhesion needed.

My uxes consisted of: Ferro frits 3124, 3134, and 3195,a good place to start in terms of readily available frits.Then in a radical move, I ignored all previous instructionand treated the colorant as one of the base ingredients.This allowed for full incorporation of the color withthe other two ingredients during the mixing of the baserecipe. I used commercial stains in order to get an opaquequality (I later tested variations with oxides that resultedin a somewhat transparent underglaze.)

I mixed 1000 gram batches in a thousand variations (orsomething close to that). I actually mixed three batchesof each recipe to testing gums and suspenders, without

which, any substance mixed from the above ingredientswould settle to a rock-hard mess and be nearly impossibleto brush onto any clay surface. I tested CMC gum (pow-der, premixed into a liquid), premixed bentonite, and StaFlo laundry starch (a tip from one of the internet recipes).

Not having the ability to replicate the colliodal process,I sieved and ball milled each recipe in order to fully inte-grate the raw materials into each other and to reduce theparticle sizes as much as possible.

I tested each glaze on leather-hard, bone-dry, andbisqued earthenware and stoneware test tiles. I red theearthenware tests to cone 04 and the stoneware tests tocone 6 and cone 10, all in an electric kiln.

Hollys UnderglazeCone 0410

Ferro Frit 3124 . . . . . . . . . . . . . . . . . . . . . . . 33.3 %

EPK Kaolin . . . . . . . . . . . . . . . . . . . . . . . . . . 33.4

Commercial Stain . . . . . . . . . . . . . . . . . . . . . 33.3 100.0 %

Sieve all materials with an 80 mesh sieve and then ballmill for at least 12 hours. Incorporate Sta Flo LaundryStarch until the mixture reaches a thin yogurt consis-tency and sieve the entire mixture again.



by David L. Gamble

Commercial underglazesare basically clay slipscontaining colorants,and theyre a great way

to add color to your work using avariety of application methods. Andsince theyre formulated to have lowdrying shrinkage, they can be ap-plied to bone-dry greenware or tobisque-red surfaces. In additionto being able to change the surfacecolor of your clay body, underglazescan also be used to change the tex-ture of the body.

When used to add color to sur-faces, underglazes have an advantagein that they are composed mostly ofclay with very little ux, so theyll

stay put and wont run, which makesthem ideal for detailed decoration.While most underglazes were origi-nally formulated for use at low-retemperatures, most, maintain theircolor in the mid-range and some evenas high as cone 9 or 10.

Simple ApplicationUnderglazes can be applied by brush-

ing, pouring, dipping, and spray-inganything goes. Each applicationmethod has different requirements. Ifan underglaze is too thick for spray-ing or using as a wash, just add waterto thin it down. If its too thin for silkscreening or monoprinting, leave thecontainer exposed to air to evaporatesome of the liquid.

Teapots , by Jim Kemp. Jim uses a low-re red clay body and airbrushes under-glazes onto the greenware. The last color he applies is black, which is sprayedacross the piece to highlight the variations in heights of the surface decoration.The pieces are once red to cone 02.

9 Artists Using ColorfulUnderglazes



Underglazes work best with a clearoverglaze, although other glazes ofvarying opacity and color may alsobe used. Ive had success with whites

and very light-colored glazes, butdarker glazes seem to muddy or ab-sorb the color of the underglaze. Theoverglaze can be anywhere from mattto glossy. Youll nd the clear deepensthe value of the colors regardless ofapplication method. If youre sealingthe surface of work that will come incontact with food, be sure to use afood-safe clear glaze that matchesyour underglazes and clay bodys r-ing range.

Applying an overglaze can betricky. If youve applied underglazeson bisque, youll nd that theyllsmear when brushing on a clear over-glaze because wet glaze moistens theunderglaze. Use a fan brush and oatthe rst coat on without going overthe same area twice. Wait for the rstcoat to dry completely before brush-ing on a second coat.

Ive recently used underglazes tocreate a watercolor effect by thinningthem down and painting them onto asemi-white glaze that is layered overanother colored glaze underneath.The colored glaze (sometimes gloss,sometimes matt) melts through thewhite and gives it a richer off-whitelook. The clay body is a red terra cottathat can handle a number of multiplerings if needed. Ive been creatingpieces from my travel sketches to per-manently document places Ive trav-

eled to in a sketchbook-like manner.

Testing the limitsThrough their testing, clay artistshave been very inuential in the in-creased use and relabeling of under-

3 Women Praying , by Debra Fritts.Debra sculpts in terra-cotta clay andbisque res to cone 02. She thencovers the piece with black stain andthen underglazes are applied, wiped,scraped, and red to cone 04. Shecontinues with nal additions and

does a nal ring at cone 05.

In this example frommy Sketch BookTravels , series, Ibisque red a clayslab to cone 03then layered baseglazes3 coatsof key lime withwhite, and 3 coatsof low-re whiteon top. The sketch

is then executedwith thinned outunderglaze washesand red to cone 04.



glazes. When they successfully ex-perimented with ring underglazesabove the recommended cone 06 toa cone 5 with little or no change incolor, manufacturers relabeled theirproducts to reect the change. Thehobby industry also helped promotehigher ranges by developing a line ofcone 5 casting porcelain, meaningmore potters were working at highertemperatures. Even though the ma-

jority of underglazes can survive acone 5 ring, usually resulting in amore vitreous surface, always testbefore using them on your artwork.

Through the years, my friends andI have done many tests, taking un-

derglazes to cone 10 in different at-mospheres. Many of the underglazeschange color and most become veryvitreous, even glossy, without a clearglaze over top. Ive even red someunderglazes at cone 11 and 12 withnice results.

At the University of Indianapolis,Dee Schaad mixed some of the newbright red and yellow underglazesinto a cone 10 clear glaze in a ratio

of three parts clear to 1 part liquidunderglaze. He then brushed themixture on top of various cone 10 re-duction glazes, including a tenmoku,with great resultsthe bright colorsstayed bright. When potters told me

Rimas VisGirda slab builds his plate forms

from a terra cotta body. Following a pencil

outline, he brushes on underglazes then ap-

plies wax to the entire surface. He redraws

the gure and the outer border by scratch-

ing through the wax and into the clay sur-

face and then inlays liquid black underglaze

into the scratched lines. After bisque ring

to cone 05, he waxes the gure portion and

outer edge again but leaves the background

alone. After sketching in owers with a pen-

cil, he applies underglazes to the owers,

leaves, and stems and further denes them

with black underglaze. He applies wax over

the ower stems and leaves then sponges

blue underglaze onto the background. After

ring to cone 5, he adds shading with an

underglaze pencil then re to cone 3.



Paul Wandless paints underglazes on plas-

ter in reverse, painting the foreground rst

and the background last. He then pours a

low-re white slip on the plaster. This picks

up the underglaze image and inlays it into

the clay. After bisque ring to cone 02, he

applies a thin clear glaze then glaze res

to cone 04.

Steve Howell uses a body made from half porcelain and half

raku clay. After the initial bisque ring, he adds underglazes

and bisque res again. Because a higher bisque absorbs less

smoke, he bisque res cool colors to cone 06 and warm col-

ors to cone 04. After the bisque, he places the piece upside

down in a 24-foot brick pit lled with sawdust layered withcopper carbonate, salt, and bits of sticks and wood, then

covered with a Kaowool blanket.

Tom Meunick uses white stoneware or porce-

lain then bisque res to cone 06. He then uses

underglaze pencils to draw on the surface. Af-

ter drawing, he atomizes it lightly with water

then applies a glaze by dipping or spraying.



Scott Rench silk screens the images he creates on his com-

puter. Those images are screened onto the clay while they

are still wet and can later be formed and shaped. After

bisque ring to cone 04, Scott airbrushes a clear glaze and

res again to cone 04.

Ron Korczyski bisque

res a white low-re

clay to cone 04 then

applies underglaze by

brush on the bisque

piece. He uses many

underglaze colors in dif-

ferent size applicators that

he can squirt out and draw

line details and dots of color. The

nal piece is red to cone 05.

that the new bright reds that re tocone 10 blush out to white, it mademe wonder if mixing them in a clearglaze would help protect them fromthe salt when salt ring. Experiment-ing with all these colors allows youto nd new and unexpected resultswhen testing in, on, and under any-thing you have on the glaze shelf.

One thing to remember, however,is that if youre using underglazesat a higher temperature than rec-ommended, things can change. Oneclay artist using a black underglazeat cone 10 noticed that the next pintshe opened looked the same in thejar but had a very greenish cast whenred. The company told her they hadto reformulate because of govern-

ment regulations and material avail-ability and reformulated the color tot their cone 06 to 5 suggested ringtemperatures. The higher cone 10temperature was overlooked and nottaken into consideration.



by Courtney Murphy

Combining clean lines and spare but playful decoration gives Courtney Murphys work an inviting, slightly retro feel.

Ive always been drawn to spare and simple forms, andmuch of my time is spent looking at textiles, artwork, andhousehold items from the mid-20th century. I have a deepappreciation for simple, well-designed industrial objects,as well as childrens artwork and folk artthings that areless rened and show the hand of the maker. In my work,I attempt to seek a balance between these two interests. Istrive for the clean lines and gracefulness, while my draw-ings and color choices are more inuenced by childrensartwork and folk art. The simplicity of the form creates acanvas for a more playful element in the drawing.

Making a Big SwitchFor many years I worked with a white mid-re clay. I usedunderglazes, drew incised lines, and created areas of coloron a white background. I liked the work that I was mak-ing, yet it didnt really feel like me. It felt somewhat tooclean and precise.

During this time, I would often take classes and work-shops focused on earthenware. It was fun to work on alarger scale, to work a little more loosely, coil building newforms and trying out new surface decoration techniques.I liked the option of working on a larger scale that earth-enware provided, and often thought about switching over,but at the end of each class or workshop, I would alwaysreturn to my white clay, where I felt more comfortable.

I spent the fall of 2009 assisting Jerilyn Virden at Pen-land School of Crafts. Jerilyn creates beautiful double-walled forms using earthenware. Living at Penland for twomonths, and working with earthenware every day providedme with the right incentive to change my clay body as wellas my style of work. It was a bit of a bumpy transition, asI tried to learn a new palette of glazes and surface decora-tions, but at the end of two months, I had a few pieces thatseemed promising.

Underglaze as Overglaze



That winter, I left for Montana to begin a two-yearresidency at the Archie Bray Foundation. Once I arrived,I immediately started testing slips and glazes. I reallyloved Posey Bacopoulos cone 04 satin majolica recipe.At Penland, we had been working with earthenware inthe 02 to cone 2 range, and Poseys glaze was beauti-ful at cone 01no longer satiny, it looked more likeenamel. Id originally envisioned using a satin glaze, butI liked the way my drawings fused into the surface of the

glaze at a higher temperature.

Waste Not, Want NotAfter all of those years working in white clay, I had ahuge supply of underglazes. I didnt want the jars to goto waste, so I started testing all of my colors over the ma-jolica to see what would happen. A surprising number ofthe underglaze colors looked great, those that didnt werevery dry or bubbled. I put a big X on those and boxedthem up, so that I wouldnt accidentally use them. Thecolors I use are mainly Amaco Velvet underglazes andDuncan underglazes. Testing is required as certain colors

will work ne, but a similar shade wont work. I oftenmix the colors that do work to create new shades.

After switching to earthenware, I started brushing twoto three thin layers of a terra sigillata on the bottom ofbone-dry work to enhance the color of the clay and cre-ate a nicer feel on the bottom ( gure 1 ). Once the sig haslost its sheen, I burnish it by wrapping a plastic grocerybag tightly around my thumb and rubbing the coated area(gure 2 ).

Glazing and DecoratingAfter the work has been bisqued to cone 0405, I beginglazing. I dont use wax, mainly because Im pretty clumsywith it. Instead I scrape the excess glaze off with a rubberrib, then sponge the rest off, leaving about inch of theclay exposed on the bottom ( gure 3 ). To cut down ondrip marks, once the glaze has dried a little, I use a softdrywall screen to sand out the larger drip marks. I alwayswear a dust mask and sand while holding the piece awayfrom myself and over a bucket of water to minimize dust(gure 4 ).

3

Applying terra sigillata to the foot of a bowl. Burnishing the terra sigillata with a plastic grocery bag.

Cleaning glaze off of the bottom with a sponge. Using a drywall screen to sand out glaze drips.

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P r o c e s s p

h o t o s : N i c

h o

l a s B i v i n s



Because the glazing and decorating process takes a while,glazing is done in small batches. I using three different col-ored versions of my base glaze: yellow, pale mint green, andwhite. I try to focus glazing with one color at a time, oth-erwise it gets confusing, as all of the glazes look the samein the bucket. This helps me to avoid touching up a piecewith the wrong color.

When I rst switched to majolica, I knew that I wouldmiss the precision of the incised lines, but found that an18-gauge slip-trailing bottle creates a very nice, ne line(gure 5 ). A 16-gauge bottle will form a thicker line. I usethis less often, but it is useful for drawing dots on pieces.I ll the bottle with underglaze and add water if neededto get a smooth ow. Before drawing on a pot, test thatits owing evenly on a piece of paper. Globs do happenoccasionally, but they are easy to clean up if you let themdry then scrape them off of the surface using a metal rib(gure 6 ). After scraping, rub out that spot with a ngerand redraw the line.

There is denitely a window of time when this processworks best. I start drawing lines on top of the majolica abouta half an hour after glazing. Line drawing comes fairly easilyas long as the glaze doesnt get too dry and powdery. Once ithas reached this stage, the slip trailer does not ow as easily.Lightly misting the glazed piece with water sometimes helps,but its much better to decorate while the glaze still has somemoisture in it.

When not in use, I plug the slip-trailing bottles with a sew-ing pin (the type with a little bead on the end). This works re-ally well, and its nice to have the pin available in case the tipgets clogged. Its important to remember to keep the pin in thetip when the bottles arent in use, because they dry out easily.

The line drawings dry really quickly. Usually Ill draw onve to six pots, then start coloring in my drawings ( gure 7 )For the painting stage, I nd it easier to pour my underglazesinto a plastic ice tray, preferably one with a lot of compart-ments. The empty compartments are good for mixing under-glaze colors together.

Using an 18-gauge slip trailer to draw lines on a bowl. Scraping off a mistake with a metal rib.

Painting with underglaze over majolica. Finished creamer and sugar with yellow majolica glaze.

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Drawing InspirationMy drawings arent planned out beforehand; I tend to work more

intuitively, looking at the space and seeing how I want to divide itup. Ive spent the last two years trying to nd the right balance be-tween too little and too much decoration.

My drawings are mostly inspired by the idea of connection. I havemoved a lot over the past several years and being in a residency situ-ation involves a lot of people moving in and out of your life. Someof these connections have stayed very strong despite the distances.My drawings often occur in groupings of two to three similar ele-ments, dotted lines sometimes connect these elements, creating linesof communication.

Im also intrigued by the new connections that are formed when apot leaves my studio to become a part of somebody elses life. I ndthis to be one of the most interesting aspects of being an object mak-er. Using pots made by friends who are far away really does help meto feel connected to them. Its a really nice part of being a potter.

To see more of her work, visit her website at www.courtneymurphy.net or herEtsy store at www.courtneymurphy.etsy.com .

Lidded jar, earthenware, majolica glaze, trailed and painted under-glaze decoration, red to cone 01.

Mels Fantastic Sig

1 Part Redart2 Parts distilled waterAdd: 0.025% Darvan 7

(.025% of the clay weight, not ofboth the clay and water combined)

1. Blunge Darvan into water.

2. Slowly add clay to water and blunge for about35 minutes.

3. Ball mill for 1224 hours (no longer or shorter).

4. Pour into clear container, let sit for 1218hours.

5. Either siphon out middle layer, or just pour offthe top 2 layers. The top layer of water shouldbe minimal so its not usually worth siphoning.

6. Simmer gently on the stove, stirring constantly,until the mixture reduces itself to about 2 / 3 itsoriginal volume. If a skin forms on the surfacewhile youre simmering it, just mix it back in. Saveall chunks of clay.

7. When the sig cools, use a brush to re-integrateall the chunks and the liquid sig. There should bea slight sheen on the surface and the materialshould brush smoothly onto bone-dry pots.

*Note: I realize this is a more elaborate sig recipethan others you might have seen. Ive tried simplerrecipes, but had a lot of problems with aking orweird textures. Finally my friend Mel Grifn gaveme this recipe and its worked really well.

PB Matte MajolicaCone 0501

Dolomite . . . . . . . . . . . . . . . . . . . . . . 10 %Ferro Frit 3124 . . . . . . . . . . . . . . . . . . 65EPK Kaolin . . . . . . . . . . . . . . . . . . . . . 20Silica . . . . . . . . . . . . . . . . . . . . . . . . . 5 100 %

Add: Zircopax . . . . . . . . . . . . . . . . . . . 10 %

*Note: Although this glaze was formulated tobe a satin matte at cone 05, I have been ring it

to cone 01. To tint the glaze I add between 16percent Mason stain.

Documents

Under Glazes 2014