Presentation is loading. Please wait.

Presentation is loading. Please wait.

April 23, 2014 BR: When Mrs. Brown gives you clay out of the bag, what stage is it in? EQ: What are the 6 Stages of Clay?

Similar presentations


Presentation on theme: "April 23, 2014 BR: When Mrs. Brown gives you clay out of the bag, what stage is it in? EQ: What are the 6 Stages of Clay?"— Presentation transcript:

1 April 23, 2014 BR: When Mrs. Brown gives you clay out of the bag, what stage is it in? EQ: What are the 6 Stages of Clay?

2 April 24, 2014 BR: What is the FIRST THING you do once you have been given clay when working with it? (ALWAYS!) EQ: What are the 6 Steps of Using Clay?

3 April 28, 2014 BR: What is the saying for applying two pieces of clay together? EQ: What is the process of scoring and slipping?

4 April 29, 2014 BR: What is slip? EQ: Is clay an additive or subtractive process?

5 April 30, 2014 BR: What are some ways to decorate clay? EQ: What is applique?

6 May 5, 2014 BR: What is a firing cycle? What is the length of a firing cycle? EQ: What are the “wares” of clay?

7 TODAY Please follow along with the PowerPoint and fill in your Ceramic worksheet. Daily grade given for being on task and participating; if you are off task/sleeping you will loose points and a possible detention. You will be tested on this information and it will also be on the final exam.

8 Bell RingerMarch 4, 2015 What is clay?

9 Comprehensive Art Mrs. Brown

10 What is Clay? Clay is......a fine mixture of decomposed igneous rock materials and organic matter. Clay is continuously being formed.

11 Over time, exposure to the elements cause the materials to break down into smaller and smaller pieces: Weathering Boulders Rocks Pebbles Fine grain = materials that make up clay.

12 Weathering Processes:

13 Objects made from any type of clay that is fired with the aid of heat

14 History of Ceramics It is hypothesized that ceramics came about when humans 1 st learned to control fire. Old methods and concepts are still used today.

15 Anthropologists use Stone Age clues to piece together a variety of possible theories of ceramic’s origin

16 Greece 1600 B.C Some jars as tall as 6 ft Created using the coil method

17 Cuneiform Script Early system of writing in Mesopotamia Stylus pressed into clay tablets Record-keeping of laws, historical events, & harvests Communication & Documentation:

18 Hunting Scene 2250-2150 BCE, Mesopotamia Form of signature, or identification on important documents. Cylinder Seal

19 Pots were widely used as funerary objects in prehistoric burial grounds Contained food to accompany dead on journey to the afterlife Infants and small children Ceramic figurines and animals to protect the deceased.

20 Terracotta Warriors Form of funerary art - buried with the First Emperor of Qin (He was the first emperor of China in 221 BCE.) Their purpose was to help him rule in the afterlife. Architects are currently still excavating

21 6 Steps to Using Clay 1.Early Preparation (Levigation) 2.Forming Clay (5 major methods) 3.Drying Clay 4.Decorating Clay 5.Glazing 6.Firing These two stages (5 & 6) can happen in reverse order as well.

22 Step 1: Early Clay Preparation Early potters dug their raw material out of the ground, and it often contained impurities such as pebbles or plant matter. To remove these, potters would dry the clay in the sun, crush it into smaller lumps, and pick out the unwanted material. Then, they rehydrate the dry clay to make it workable. This method was fine for making a few pots, but it was difficult and time-consuming. ** The clay that Mrs. Brown gives you has already been through this early clay preparation process.

23 Modern Clay Preparation Potters discovered it was much easier and faster to separate impurities by adding water to the clay and then pouring the liquid clay (slip) from one container to another. This process is known as decanting. Decanting causes the coarser materials to settle on the bottom. Another traditional method for removing impurities is known as Levigation.

24 The earliest and simplest methods are still used today. Four Basic Hand Building Techniques: 1.Pinch Method (oldest method) 2.Coil Method 3.Slab Method 4.Molding Method

25 Hand Building : Process of forming pieces using hands without the use of a potter’s wheel; 30,000 years old.

26 Pinch Method Is when clay is pulled and pinched in order to shape an object with fingers. It is the oldest form of ceramic hand building.

27 Pinch Pot

28 Pinch Method:

29 Two Pinch Pots Combined to create a hollow form:

30 Coil Method Created through long ropes/coils of clay that are of equal thicknesses are used to build a ceramic object

31 Coil

32

33 Slab Method A method of rolling out clay flat to an equal thickness. Slabs can be cut into shapes and used to construct ceramic objects.

34 Slab Method

35

36

37 Throwing: A method of forming clay in which the sculptor uses a pottery wheel. Throwing is NOT a technique of hand-building.

38 Potter’s Wheel : A machine that forms pottery using a wheel

39 Step 3: Drying Clay Potters must know how to control the rate at which clay dries. Clay shrinks as it dries and, if it shrinks too rapidly, it can crack. Clay that has dried to this point is in the leather-hard stage; when pressure is applied to the clay, the form will not easily distort. See the following Stages of Clay.

40 6 Stages of Clay 1.Slip 2.Wet/Plastic 3.Leatherhard 4.Bone-Dry ~Firing~ 5. Bisque (Bisqueware) ~Firing~ 6. Glazeware (Glazenware) Stages 2 – 4 are also known as Greenware.

41 1.Slip: Liquid clay; “glue” required to attach two pieces of clay together. 6 Stages of Clay

42 2.Wet: Plastic clay; workable; easily manipulated. ** IDEAL * When Mrs. Brown gives you clay out of the bag it is in this stage. 6 Stages of Clay Con’t

43 3. Leather Hard: Clay is stiff but still damp; firm -maintains form and can be smoothed, carved, and added to. *not easily distorted, but can still be carved.

44 6 Stages of Clay Con’t: 4. Bone-dry: Water has evaporated from the clay; form is brittle and ready to be fired. ** Clay becomes lighter in color

45 6 Stages of Clay Con’t 5.Bisque (Bisqueware): fired once; ready to be glazed then fired a second time.

46 6 Stages of Clay Con’t 6. Glazeware: Objects that have been fired a second time after glaze has been applied.

47 Clay may be recycled through the Bone Dry stage by simply rehydrating it. R*E*C*Y*C*L*E : **Once clay has been fired it becomes permanent – it can no longer be recycled.

48 Impressing uses an object to press or stamp a design into the clay. Combing marks the surface of the clay with uniform lines. Burnishing involves rubbing and polishing the surface with a smooth stone or piece of hard wood. Step 4: Decorating Clay

49 Incising – Carving or cutting into the clay surface with a tool.

50 Step 5: Glazing Glaze: A coating of liquid glass that is applied to a clay surface that melts together and forms a decorative and protective surface.

51 Glaze also makes your ceramic piece: Colorful Food Safe (check glaze label.) Water Proof

52

53 Step 6: Firing The earliest pottery was fired in open fires.

54 Firing Methods The main methods of firing clay are: Open Firing: in which the vessels and fuels are set together. Kiln Firing: in which the vessels and fuels are separated.

55 The Kiln: Chamber for firing your clay. Clay MUST be Bone Dry to fire. You must fire your clay for it to become permanent.

56 Kiln (Con’t) A kiln can reach temperatures of 2,500 degrees F and higher. Your oven at home possibly reaches 500 degrees - at the most.

57 The Kiln

58 8-12 hours = to heat to maximum temperature. + 8-12 hours = to cool 16-24 hours for firing cycle. ** That’s why it takes longer to get your Ceramics projects back.

59 What are the 3 Variables of Clay? 1.Plasticity 2.Moisture 3.Heat

60 Plasticity: Workability Is the quality of clay that allows it to be easily manipulated and still maintain its shape. Ideal texture for clay = similar to play-dough

61 The ability to hold together while being shaped (workability) - Does it stretch and bend without breaking? - Test It! Wrap a coil around your finger. If it cracks, the clay is not plastic. Plastic Not Plastic Create the Coil

62 All clay contains water. Clay dehydrates when exposed to air. Add water to clay to make it more plastic. Too little or too much water causes clay to become less plastic. Tip: Mist clay with damp sponge. ALWAYS wrap your projects with plastic (and/or a wet cloth) before storing. Moisture

63 Fire or heat makes the shape permanent and returns the clay to its rocklike state. Firing at temperatures ranging between 500 - 800 degrees Fahrenheit changes the physical state of clay mineral crystals into a hard, stable medium. When clays are heated above these minimum temperatures, they become ceramics. Heat

64 Other Ceramics & Clay Vocabulary To Know:

65 Kneading: Process of pushing clay together.

66 Wedging: Process of slamming, kneading, or pushing clay together.

67 1.Removes air bubbles trapped in the clay. 2.Equalizes moisture. 3.Makes clay texture uniform. 4.Re –forms smaller pieces into one big one. **You MUST ALWAYS wedge/knead first BEFORE using your clay.

68 Score: Means the process of roughing up the edges of clay with a tool in order to join two pieces of clay together. You must always: “score, slip, and press” when joining any two pieces of clay together.

69 Functional = pottery that serves a purpose or does a job. Examples include: dishes, vases,bowls, cups or plates.

70 Aesthetics: The visual beauty or pleasurable qualities of an object.

71 Sculpture in the Round: A freestanding sculpture that is meant to be seen from all sides. Chris Gustin

72 Golden Rules of Ceramics: Always WEDGE/KNEAD clay first. Score, slip, and press ALWAYS when joining two pieces of clay. No trapped air! – poke escape hole! Clay must be no thicker than the tip of your thumb. Always cover clay fully so that it will not dry out.


Download ppt "April 23, 2014 BR: When Mrs. Brown gives you clay out of the bag, what stage is it in? EQ: What are the 6 Stages of Clay?"

Similar presentations


Ads by Google