Ceramic Dictionary: H

HAIR

Hair grows out from the skin of mammals and covers different parts of the body. Hair is made up of hundreds of very fine strands that grow together. They differ in texture, color and thickness with each animal

Animal hair is used for the heads of brushes for painting, cleaning etc. For working in ceramics, there are many different brushes made up with different hairs in varying sizes and shapes to leave different brush strokes and for work in special styles. In the ‘Brushes’ section there are photos of the different types with their names.

Synthetic hair is now commonly used in many paintbrushes and is more economical to buy. When you buy, make sure you know what you are buying. See: Brushes – decorating

HAKE BRUSH

ca: HAKE BROTXA

es: HAKE PINCEL

Hake brush is a soft, flat, wide Chinese brush useful for applying slips and glazes and also good for dusting work that is prepared but unfired.

HAMMER

ca: MARTELL

es: MARTILLO

Hammers is a tool with a head attached crosswise on to the top of a handle and used for beating one object into another, like a nail into wood or a pole into earth. It is usually made of metal or wood.

Hammers made as kitchenware are also used for ceramics. They are wooden, of different shapes, sizes and textures and are used for beating down clay and to indent textures. There is a similar tool, usually in wood, used for driving in other tools that have a wooden handle, such as chisel. It is known under the name of mallet

HAND PAINTING

ca: PINTAR A MA

es: PINTAR A MANO

Hand painting is to decorate and paint on to an object by hand without using any form of process such as transfers, screen printing, etc.

HAND POLE

ca: BARRA – Suport per la mà

es: BARRA - Soporte para la mano

A hand pole is a long, round, thin and strong bar that can be made of wood, plastic or metal. Mop handles are good, because some allow you to alter the length.
In ceramics they are used for steadying your hand while painting, sitting or standing and must be long enough to paint the highest line of tiles you can reach while standing.
Hold it in your left hand if painting plates and rest it against the edge of the table. When working with tiles the bar supports them or if necessary put your left hand small finger on a clean part of a tile. With your right hand, hold the pole with your small finger and the paintbrush with your thumb and first finger. Depending on where you want to paint, you can now move your right hand up and down and bend the pole from left or right or move it.

A Mop handle, is used as a hand pole when painting. It is good as you can alter its length and it is not heavy. Put a clip to hold it onto the wall or the table near to where you are working. If it is a table it should be put on the left, so it does not interrupt the movements of your hand between whatever you are decorating and the trolley-table where you keep everything you need. The photos show it in relation to the table, the hand pole opens and shuts so you can compare the different lengths and you can see the clip to keep it when not being used.

HAND-BUILDING

ca: CONSTRUCCIÓ MANUAL

es: CONSTRUIDO A MANO

Hand–building is building structures in clay by hand. Pots and sculptures are created by using methods such as coiling, pinching and slab building. See: Coiling – Coil Building / PINCHING – Pinching clay into a bowl. / PINCHING – Pinching plus coiling clay into a bowl / SLAB – Building boxes

HANDLE

ca: NANSES

es: ASAS

Handles and how they are attached to a pot, plate, bowl or jug should be thought of as an overall part of the design, a functional and decorative asset, there are three types of handles, Loop, Lug and Knob which is round.

a) A loop handle is made with a separate piece of clay which is added to the side or lid of an object and always has enough space between it and the main body big enough to be held by hand while being moved.

b) A lug handle has little or no space between it and the main body it can be made in two ways by making the lug separately and attaching it or joining the clay to the maid body and pulling it. The illustration it is seen from above.

c) A knob is a small handle made to put on the top of lids and they are also used on the sides as a handle- There are different types of knobs and are explained in the section lids.

With a teapot which has a spout or a jug with a lip the handle must be place at 180º or 90º in relation to them for pouring out the liqued. With a piece that is round it can be attached to any part of the outside wall.

Note: It is very difficult to define these sections as pottery language is different from the language of every day. In everyday language the words lug and loop would never be used, the two words normally used are knob and handle.

HANDLES - Loops

ca: NANSES – Estiratge

es: ASAS – Estirado

Click on the title to see more images

a) With an oblong lump of clay, hold it with your left hand pull it down with you right, thinning slightly until there is enough for the handle.
b) Lay it on the edge of the table separate it, slicing it with your hand.
c) Score and add slurry to parts that have to be joined.
d) Support the inside of the neck with your left hand to take the pressure of attaching the clay on the outside, push the cut end firmly onto the jug.

e) Turn the jug sideways, support it underneath and with you right hand pull the clay downwards, between you thumb and fingers flattening it slightly.
f) Continue pulling and narrowing it until it is the length and shape you want.
g) Stand the jar up, support the and shape the handle with your left hand and with you right the attach it at the bottom with a few strong strokes.
h) The handle finished.
The following photos show some of the different ways of designing a handle.

HANDLES - Lug attached

ca: NANSES – En forma d’anella

es: ASAS – En forma de anilla

Click on the title to see more images

Lug handles: are small separate pieces of clay attached to casseroles and bowls with none or very little space between the lug and the wall, never enough for fingers to pass. There are two types and they are made with soft clay and applied to leather dry clay.
1) The lug is shaped separately a).
2) The part where it is going to be attached must be looted and dampened with slip.
3) Holding the lug press it firmly over the luted part and with a finger of your right hand press the edge of the top against against the neck of the jug, then underneath edge is pressed down and smoothed off. b).
4) Supporting the neck from inside the lug is shaped c).
5) The lug finished d)

HANDLES - Lug pulled

ca: NANSES – Anella estirada

es: ASAS - Anilla estirada

1) Mold the clay into a thin, rectangle with round corners to the size needed.
2) Damp with a sponge the parts where is has to be joined.
3) Hold it vertically and attach the bottom left hand side, pressing and smoothing it out. (a)
4) Bend it horizontally, when you do this the outer edge will bend out wards and connect the other end in the same way as the first. (b)
5) The lug finished. c) The part between the two ends is touching the pot but not joined to it.

HANDMADE

ca: FET A MA

es: HECHO A MANO

Handmade is used to imply that a product is not made in any way by a machine but by human hand.

HARP

ca: ARPA

es: ARPA

Harps are tools to trim and cut small slices in clay and are made of metal. They form three sides of a rectangle and have evenly placed notches at the bottom of each leg, in which a thin wire is held that connects the two sides and allows it to slice lumps of clay at different levels. The legs should be on the table, one on each side of the clay as it is pulled through, slicing in a straight line and separating the clay into two sections. For cutting large pieces. See: Slab – Cutter
.

HARRISON PYROMETRIC CONES

ca: HARRISON PYROMETRIC CONOS

es: HARRISON PYROMETRIC CONOS

Harrison is the name of a firm that makes pyrometric cones. See: CONE – Pyrometric

HEALTH

ca: SALUT

es: SALUD

Health. Great care should be taken when working in ceramics. Masks, goggles and gloves should be used, not only when preparing products but when cleaning up. Sweeping throws dust and products into the air, which can be inhaled. For cleaning, a strong industrial vacuum cleaner is much safer than a broom

HEAT

ca: CALOR

es: CALOR

Heat is the degree of hotness, which can increase and decrease and is controlled by an energy that causes a rise in temperature, such as gas or electricity. With different products andx at different temperatures, it causes expansion, evaporation and other physical changes. In ceramics, it changes clay, a soft, pliable product, into a hard breakable one and colors from powder into a glazed, non absorbent, breakable surface.

HEAVY

ca: PETAS

es: PESADO

Heavy is when a product has much weight in proportion to its size.
Heavy is also used to describe a line or form that is broad, thick, or coarse; not delicate:

HIGH FIRING

ca: ALTA TEMPERATURA

es: ALTA TEMPERATURA

High firing is when glazes and colors are prepared to exceeds 1200º C when being fired.

HIGH-TEMPERATURE GLAZES

ca: ESMALTS D’ALTA TEMPERATURA

es: ESMALTES DE ALTA TEMPERATURA

High temperature glazes is when glazes and colors are prepared to exceeds 1200º C when being fired.

HISPANO-MORESQUE WARE

ca: HISPANO-MORISQUES CERÀMICA

es: HISPANO-MORISCAS CERÁMICA

Hispano –Moresque is a name given to two methods; Luster and Majolica, because they came to Spain through the Moorish occupation. They brought two methods of decorating ceramics that when fired look very similar, but the way of working is completely different.

Lustre is bisque, fired clay, covered with an opaque glaze-base that is fired, it is then decorated with colors made up from precious metals and fired again between 700 and 800 Cº.

Majolica is bisque, fired clay, covered with an opaque glaze-base and decorated. Both are fired together integrating the colors. They were made originally for the rich ruling classes but Majolica was more economical and became a more popular product. In the dictionary the method Majolica has many sections. The one shown here covers the basic way of working.
See: Lustre On-Glaze / MAJOLICA: 3 – Decorating

HOLE

ca: FORAT

es: AGUJERO

Click on the title to see more images

Hole is an opening through or into something, a hollow place in a solid body that can be accidental or designed.

a) Plate back, holes to hang it up. See: Footings – Classic with throwing (13)
b) Sun clock, hole for the arm that reflects the shadow to tell the time. See: Drilling Holes
c) Plate with holes as a decoration. See: Pierced – Decoration
d) A liquid container with two holes, for pouring small and large quantities.

HOLE CUTTERS

ca: TALLADOR DE FORAT

es: CORTADOR DE AGUJERO

Hole cutter is a tool to pierce holes and dig out clay in general decorating. They are made in different sizes, with a handle and a stainless steal head which is a round empty tube, cut at the top at 45º.

HOLE PIERCER

ca: PERFORADOR DE FORAT

es: PERFORADOR DE AGUJERO

Hole cutter is a tool to pierce holes into clay, for lamps where the wire has to pass, for tea pots and for general decorating into clay.

There are two types:
a) The main one is made in different sizes, with a handle and a stainless steel blade which is long, solid, straight, finishes with a point and has indenter’s length wise to prevent clogging.
b) Is basically the same, only small ones are made and the whole blade is round tapers to a point.

HOT

ca: CALENT

es: CALIENTE

Hot a when something has high temperature or gives off heat and is the point before burning.

HUMP MOLD

ca: MOTLLE D’ASSENTAMENT

es: MOLDE DE ASENTAMIENTO

Hump mold is a mushroom shaped mold with a convex surface to make dishes.
See: Mold: 1 Press molds

HYDRATE

ca: HIDRATAR

es: HIDRATAR

Hydrate is to combine a chemical with water. Both clay and glazes hold water which dries out during the first stages of firing. The firing should be slow to begin with and when it reaches 600ºC they should be dry. Quick firing of clay can cause cracking and breaking and the crawling of glazes.

HYDROMETER

ca: HIDRÒMETRE

es: HIDRÒMETRE

Hydrometer is an instrument used to measure the specific gravity (or relative density) of liquids; that is, the ratio of the density of the liquid to the density of water.

A hydrometer is usually made of glass and consists of a cylindrical stem and a bulb weighted with mercury or lead shot to make it float upright. The liquid to be tested is poured into a tall jar and the hydrometer is gently lowered into the liquid until it floats freely. The point at which the surface of the liquid touches the stem of the hydrometer is noted. Hydrometers usually contain a paper scale inside the stem, so that the specific gravity can be read directly.