RAKU BATIK WITH SCULPTURAL ELEMENTS USING LATEX RESIST

This article demonstrates, step-by-step, the process of using smoke, in a raku firing, to create a design with the latex resist technique. I use the term Raku Batik to replace the more common term ‘Naked Raku’ as I feel it describes both the process and result more effectively. The resulting surface has more in common with Batik (design created when color penetrates a crackled surface resist), than the images that arise with the term ‘naked.’ When I talk to potters about doing a workshop on Naked Raku, they ask if we will all be naked during the raku firing. Such an experience may or may not be desirable, yet either way it does not reflect the work we are creating.
I would first like to thank David Roberts who so graciously introduced and taught many of the techniques described here at a seminar I took with him in Arizona a couple of years ago. He has opened up a new and unlimited area for play and experimentation which I follow along with my other work in cone 10 stoneware.
I begin this demonstration with a thrown, leather hard, black mountain stoneware pot. The scope of this article does not include instruction on throwing.

Leather hard pot with Tools for adding sculpture​

Step 1: With a pencil, I draw the outline of the sculptural element I wish to sculpt on the side of the pot. On this pot I will sculpt a high relief of a Mojave Green Rattlesnake

Step 2: Using the needle tool, I crosshatch the entire area of the design where I will be adding clay. It is very important to scratch the clay deep and strong, adding some water and then scratching again. The idea is to create a thick layer of slip on the pot so that the added clay will stick well. I have seen hundreds of pots whose surface elements have fallen off due to insufficient cross-hatching and moistening. There is no point in doing all this work if the end result falls apart. Patience and thoroughness are two lessons ceramics teaches us.

Step 3: Once the pot is crosshatched and wet, the clay coil is added and joined carefully to the pot. Be sure to press the added clay onto the crosshatched area firmly and from the center out to avoid trapping air and to insure a good bond.

Step 4: The added coil is then smoothed with fingers and then a piece of sanding screen. It is further refined with a kitchen scrubber and then texture is added with the sanding screen.

Step 5: Next a large oval piece of clay is added for the snake’s head. This is joined on carefully (add water if needed. If the clay is soft then added water is unnecessary) and shaped with fingers and a flat tool.

Step 6: Next the details of the snake’s head are sculpted in with a thin, flat tool. I use a very inexpensive plastic tool with a flat, rounded shape.

Step 7: The clay is now added for the rattle and smoothed carefully onto the pot as before, with cross hatching and wetting the pot and adding the soft, moist clay.

Step 8: The sculpting portion is now complete. I have redone some of the texture using the sanding screen by pressing it into the body of the snake. I have also burnished the sides of the pot by using the back of a plastic spoon to compress the clay molecules and create a sheen on the surface of the pot.

Step 9: The pot is now left to dry thoroughly and then fired to bisque at cone 05.

Step 10: Wipe off any dust with a damp sponge. I then draw the snake design markings with a pencil and when satisfied I use a fine point sharpie to outline the forms so they don’t smudge off while I handle the pot and apply the latex resist. I then paint in the areas with the liquid latex. I fill in the diamonds and also paint a latex outline around the snake body with at least 2 coats. The latex will be removed after the slip and glaze are applied so these areas will be bare clay, receiving a strong, dark color from the smoke when in the reduction chamber after firing and removal from the hot kiln.

Step11: With a fan brush I paint the outside of the pot and the inside top of the pot (down to the lower rim) with two coats of a resist slip made from the following formula:
Resist slip
3 parts Grolleg China Clay
2 parts flint
Mix dry ingredients by volume and add water to a creamy consistency.

Step 12: When the slip is dry I then pour a low fire crackle glaze into the inside of the pot, swish it around and then pour it out. I want the inside of the pot to be glazed so it will hold water, that’s why I did not put any slip on the inside of the bottom of the pot. Then with the fan brush I paint two coats of the glaze over the rest of the pot. So now we have the resist slip painted on and the crackle glaze painted over the slip. The slip will keep the glaze from sticking to the pot yet still allow the smoke to penetrate the pot’s surface wherever the glaze crackles. This where the idea of Batik comes from. In Batiking fabric, the artist dips the fabric in wax and when the wax dries, the fabric is crushed and the wax crackles. It is then immersed in dye and the dye penetrates the fabric wherever there are cracks in the wax. In our ceramic process, the smoke (our color) penetrates the cracks in the glaze. In the picture above we see how the pot looks after the slip and glaze are applied. The areas of painted latex are easily visible. The glaze has a tendency to settle out and should be mixed with the brush before each brush stroke is applied. The glaze recipe used here is:
Glaze recipe:
Frit 3110 85%
China clay 15%
Mix dry ingredients by weight. 2% bentonite can be added to dry ingredients to help prevent settling. A small amount of Soda Ash can also be added to the liquid mixture to help keep particles in suspension.

Step 13: With a teasing needle or Xacto knife, pick up and remove the latex. If two coats were applied, it should come off easily, leaving those areas of clay bare. These areas will be fully exposed to the burning paper in the reduction chamber and will be more or less blackened. The pot is now ready for the raku firing.

Visitor from the inferno

Step 14: I am standing in front of our school’s Skutt electric kiln. At home I do my firing in a small propane fired kiln created from an old electric kiln shell. You can use either electric or gas. If you use an electric kiln, be sure to turn the kiln off before opening or removing red hot ware. If you leave it on and put your tongs on the coils you would be in for a drastic and possibly lethal shock. I wear heat resistant glove, a heat resistant apron and lots of tight fitting clothes. I wear an high quality mask to avoid smoke inhalation and a welder’s mask to protect my eyes from heat and smoke. I fire the kiln up to cone 010, hot enough for the glaze to melt but not hot enough for the glaze to fuse to the slip. I have fired it up to cone 05 but at this temperature the glaze was very difficult and at times impossible to scrape off the pot as it fused to the slip and in places to the pot itself.

Step 15: I open the kiln when it reaches temperature, reach in carefully with my tongs and take the pots out and place each before a garbage bin filled with shredded paper. I put the pot on the ground and go back and close the kiln lid. I want the pots to sit in the air for a few minutes so the colder air contributes to the glaze crackling.

Step 16: I place the pot into the garbage bin filled with paper and then cover the top of the pot with more paper. I let it flame for a few moments and then cover the bin with a lid and weigh the lid down with a kiln shelf. Now the pot will be reduced (oxygen deprived) and smoked. The smoke will blacken the bare clay areas and penetrate the crackles in the glaze. I leave the pots to smoke for an hour or so.

After an hour or so I take the lids off and remove the pots with tongs and place them on the ground to cool for awhile. Some people dunk the pots in water but for Raku Batik this does not serve any purpose but to speed things up and also increase the chances of the pots breaking. Patience is a virtue learned well in Ceramics. I keep wearing the face mask as there is still enough smoke to be unhealthy.

After an hour or so I take the lids off and remove the pots with tongs and place them on the ground to cool for awhile. Some people dunk the pots in water but for Raku Batik this does not serve any purpose but to speed things up and also increase the chances of the pots breaking. Patience is a virtue learned well in Ceramics. I keep wearing the face mask as there is still enough smoke to be unhealthy.

Step 17: After the pot cools (it may be still a bit hot so pick it up with gloves) it is covered with soot. Take it to a sink and wash off the soot with a sponge and/or a scrubber. Then, using a metal rib, scrape off the glaze. It usually comes of easily but at times requires some persistence. After the glaze is removes the resist slip needs to be scrubbed off. I use a fine wire brush and do it in a tub full of water. Don’t do it under a running faucet as that wastes water. After it is well scrubbed off it can be washed under running water for a moment.

Step 18: Once the pot is dry, I then spray it with clear satin, water based Polycrilic by MinWax. I spray 3 coats to seal and protect the surface without getting the pot too shiny.

Lewis Goldstein, MFA, is full-time Ceramics Instructor at Barstow Community College. He studied Ceramics at the University of Hawaii with great artists including Sally Fletcher, Claude and Suzi Horan, Shige Yamada and Harue McVay. He has been a ceramic artist for over 40 years and has taught stoneware, raku, porcelain doll sculpting and design, mold-making for potters, etc worldwide.


If you are interested in workshops call Lewis at 503 750 4676. You can view some of his recent work at www.lewisgoldsteinceramicarts.com and www.lgoldsteinarts.com